In late 2006, the writer John Green came up with the idea of communicating with his brother, Hank, for a year solely through videos posted to YouTube. The project wasn’t quite as extreme as it sounds. John, who was then twenty-nine, and Hank, who was three years younger, saw each other about once a year, at their parents’ house, and they typically went several years between phone calls. They communicated mainly through instant messaging. Hank was living in Missoula, where he’d started a Web site about green technology. John was living on the Upper West Side while his wife, Sarah Urist Green, completed a graduate degree in art history at Columbia. He had published two young-adult novels, “Looking for Alaska,” in 2005, and “An Abundance of Katherines,” in 2006, and was working on a third. Like the best realistic Y.A. books, and like “The Catcher in the Rye”—a novel that today would almost certainly be marketed as Y.A.—Green’s books were narrated in a clever, confiding voice. His protagonists were sweetly intellectual teen-age boys smitten with complicated, charismatic girls. Although the books were funny, their story lines propelled by spontaneous road trips and outrageous pranks, they displayed a youthfully insatiable appetite for big questions: What is an honorable life? How do we wrest meaning from the unexpected death of someone close to us? What do we do when we realize that we’re not as special as we thought we were? Green was more forgiving toward adults than Salinger was, but he shared Salinger’s conviction that they underestimate the emotional depth of adolescents. Green told me, “I love the intensity teen-agers bring not just to first love but also to the first time you’re grappling with grief, at least as a sovereign being—the first time you’re taking on why people suffer and whether there’s meaning in life, and whether meaning is constructed or derived. Teen-agers feel that what you conclude about those questions is going to matter. And they’re dead right. It matters for adults, too, but we’ve almost taken too much power away from ourselves. We don’t acknowledge on a daily basis how much it matters.” Y.A. novels are peculiarly well suited to consideration of ethical matters. It seems natural when a high schooler like Miles Halter, of “Looking for Alaska,” is depicted struggling to write essays on topics like “What is the most important question human beings must answer?” Miles is equally preoccupied with girls and with collecting the dying words of famous people. (His favorite: Rabelais’s “I go to seek a Great Perhaps.”) Though “Looking for Alaska” sold modestly, it won the Michael L. Printz Award, the American Library Association’s honor for best Y.A. book of the year. At the time, Green was living in Chicago, working at the association’s magazine, Booklist, where he had reviewed books in a peculiar constellation of subjects: conjoined twins, boxing, and theology. Upon graduating from Kenyon College, in 2000, Green had thought of going to divinity school, and he worked for six months as an apprentice chaplain at a children’s hospital in Columbus. He found the experience almost too sad to bear, and decided that such a life was not for him. Still, he remained deeply interested in spiritual matters, with one exception: “Is there a God?” struck him as “one of the least interesting questions.” After “Alaska” won the prize, Green quit his day job. He got more writing done, but he missed the intellectual camaraderie that he’d always had with his peers. The YouTube project was, in part, an attempt to fill that void. (It was also a smart marketing stunt, though Green could not have predicted how smart.) Hank had reservations about becoming the repository for John’s excess energy. He told me, “I found John exciting and smart and interesting but also a little dramatic. He gets frustrated easily. He’s anxious. Hypochondriacal.” At the same time, he said, “John, for me, has always been the baseline of what was cool and valuable and important. If he liked a band, I’d buy all of their CDs and memorize them and become a bigger fan than he ever was.” In 2006, YouTube was entering its second year, and people were starting to post video diaries, which, in their more theatrical moments, looked like performance art staged in somebody’s basement. John Green was a fan of several such series, especially “The Show with Zefrank,” which enlisted viewers in quirky projects, such as dressing up their vacuum cleaners as people. Hank shared John’s enthusiasm for these experiments, and it trumped any hesitations that he had. “We really believed in the importance of online video as a cultural form,” Hank said. The Greens started posting videos several times a week, under the name the Vlogbrothers. The project was less a conversation than an extended form of parallel play. They shared personal stories—John confessed that the only sports trophy he ever got was made by his parents, and bore the inscription “All-Star in Our Hearts”—but mainly they exchanged ideas. The brothers had signature preoccupations, which they discussed with excitable urgency, talking into the camera at tremendous speed. John discussed books, existential anxiety, and pizza; Hank was into science, math, and corn dogs. John invented a highly undignified “happy dance”; Hank wrote and performed songs, many of them about Harry Potter. The tone of their monologues ranged from goofily informative (how giraffes have sex) to wonkish (“Why Are American Health-Care Costs So High?”). Many posts dispensed adult wisdom, but in a reassuringly modern way. In a post advising boys on how to charm a girl, John jokingly said, “Become a puppy. A kitten would also be acceptable or, possibly, a sneezy panda”—an allusion to a popular clip on YouTube. But he also said, “If you can, see girls as, like, people, instead of pathways to kissing and/or salvation.” The Greens’ vlogs were filled with in-jokes and code words that rewarded dedicated viewing. “D.F.T.B.A.” stood for “Don’t Forget to Be Awesome,” and John referred to his wife as “the Yeti,” because she was much talked about but—by her choice—never seen on camera. When a brother broke a rule that they’d established, such as posting a video longer than four minutes, the other brother could impose a punishment. Hank once had to spend fifteen consecutive hours in a Target; John had to eat a generous helping of “slobber carrots.” (His toddler, Henry, provided the slobber.) In February, 2007, John was stuck at the Savannah airport, and he spotted an arcade game called Aero Fighters. He initially misread the name as “Nerdfighters,” and later, in a video, he started riffing: what if Nerdfighters were a real game? As he put it, “The band geek would be, like, ‘I will destroy your ears with my tuba!’ And the theatre guy would be, like, ‘I am an expert at sword fighting!’ And the English nerd would be, like, ‘Hmm, I know a lot of Shakespeare quotes!’ ” Why did people still pick on nerds, anyway? Who did the popular guys have on their side—George W. Bush and Tom Brady? Green declared, “I raise you an Abraham Lincoln and a Franklin Delano Roosevelt and . . . an Isaac Newton, a William Shakespeare, a Blaise Pascal, an Albert Einstein, an Immanuel Kant, an Aristotle, a Jane Austen, a Bill Gates, a Mahatma Gandhi, a Nelson Mandela, and all four Beatles. We win.” Fans loved the term “nerdfighter” and started using it to identify themselves. Initially, Green talked about nerdfighters with a hostile edge: they stood against the popular people. But the word soon took on a more celebratory, inclusive cast. Nerdfighters weren’t against anything; they were simply proud to immerse themselves in interests that others might find geeky or arcane. Indeed, the nerdfighter community is strikingly civil and constructive for an Internet subculture. Through an annual charity event, the Project for Awesome, nerdfighters have raised hundreds of thousands of dollars for one another’s favorite causes. Their comment sections, on YouTube and elsewhere, are filled with earnest suggestions for further reading and mock complaints that Green has made them care about a distant war that they’d been ignoring. Rosianna Halse Rojas, a pioneering nerdfighter, recalls the moment the concept caught on. “It was like the formation of a nation,” she told me. “Only we weren’t fighting anybody to do it.”

On June 6th, Twentieth Century Fox releases “The Fault in Our Stars,” the movie version of John Green’s wildly successful 2012 novel about teen-agers with cancer. “T.F.I.O.S.,” as fans call it, has been on a Times best-seller list for a hundred and twenty-four consecutive weeks, and has spent forty-three weeks as the No. 1 Y.A. book. The trailer for the movie, which stars Shailene Woodley and Ansel Elgort, has been viewed nearly twenty million times. Publishing executives talk about successful books as if they were lightning strikes, but the popularity of “The Fault in Our Stars” was no accident. Nerdfighters, who by then numbered in the millions, were evangelical about it, tucking notes into copies of the book and encouraging readers to join their movement. In fact, “The Fault in Our Stars” reached the No. 1 position on Amazon six months before it was published, when Green announced its title online. Many authors do pre-publication publicity, but Green did extra credit: he signed the entire first printing—a hundred and fifty thousand copies—which took ten weeks and necessitated physical therapy for his shoulder. In recent years, whenever Green has appeared at a book signing he has been greeted by hundreds, often thousands, of screaming fans, mostly teen-age girls. The weirdness of this is hard to overstate. Green is a writer, and his books are not about sexy vampires. “Stars” is a novel about young people with a deadly disease; its title is taken from Shakespeare, and it has an uncompromising ending. In the movie, as in the book, the lead character, Hazel Lancaster, wears an oxygen tube in her nose. Green did not write the film’s script, but he was an informal consultant, and it was important to him that the film retain this detail: “It flies in the face of the notion that romance, particularly about teen-agers, has to be straightforwardly ‘aspirational,’ as they always say.” Green, now thirty-six, is thin and tall, with light-brown hair that shifts around like a haystack in a stiff wind; he often rakes his hands through it, causing random clumps to stand up straight. He has the charm of the middle-school teacher you secretly thought was cute, but he is no match for Elgort, the twenty-year-old who plays Hazel’s romantic interest, Augustus Waters. I attended a preview of the movie in Manhattan this spring. Thousands of fans had lined up for free tickets, and, after the screening, they screamed when Elgort strode down the aisle for a Q. & A. But they screamed louder for Green. “We love you, John!” they called out. When Green told the crowd that, though he was proud of the movie, it wasn’t his movie, someone shouted, “But it’s your plot, John!”—which marked the first time I’d ever heard heckling about the nature of authorship. One questioner, who had to apologize for hyperventilating as she spoke, asked the five actors onstage to name their favorite lines from the book. Woodley was partial to “I fell in love the way you fall asleep: slowly, and then all at once”; Elgort cited “The world is not a wish-granting factory.” I had never watched a movie in a theatre where there was mass crying—not discreet nose-blowing, or stifled sniffles, but wracking sobs. (I was not immune.) Green told me that he had loved and hated Erich Segal’s “Love Story” when he read it in high school, and that he had wanted to write “an unsentimental cancer novel.” A story about dying teen-agers would be too wrenching, he decided, if it weren’t also romantic, and funny in a way that offered “some basis for hope.” Much of the novel’s vibrancy comes from the first-person voice of Hazel, which is irreverent but never nihilistic. After she reads online tributes to a girl who’s died of cancer, Hazel observes that the girl “seemed to be mostly a professional sick person, like me, which made me worry that when I died they’d have nothing to say about me except that I fought heroically, as if the only thing I’d ever done was Have Cancer.” When Green initially tried to write about kids with cancer, he centered the narrative on a young chaplain—“the worst kind of wish-fulfillment version of me.” The result, he once said, was “like a terrible ‘Grey’s Anatomy.’ ” Then, in 2007, he became aware of a girl from Quincy, Massachusetts, named Esther Grace Earl, who was one of the earliest nerdfighters. Esther had thyroid cancer, as Hazel does in the book, and was dependent on an oxygen tank. Green got to be friends with her online, and later visited her in person. Green is careful to say that Hazel—whose middle name is Grace—is not Esther, but Esther’s father and sister have spoken, appreciatively, of how much Green’s creation reminds them of her. Esther died in 2010, at the age of sixteen. “I could not have written it without her friendship,” Green said, adding that “there is definitely something weird about her not being here to give her blessing or not.” (“This Star Won’t Go Out,” a collection of writing drawn from Esther’s journals, letters, and blog posts, came out in January from Green’s publisher, Dutton, with an introduction by him.) When Green finished the manuscript of “Stars,” he and his editor, Julie Strauss-Gabel, felt that they had something special. Most Y.A. readers are girls, but because Green is male and his first books featured boys as protagonists his new novel seemed capable of reaching both genders. “Stars” is a love story, but Strauss-Gabel successfully pushed for a cover that did not look like a traditional Y.A. romance: no pink, no photograph of a pretty girl. Instead, the title dominates, and the background is blue. The stripped-down cover also meant that adults could read it on the subway without embarrassment. Adults have become big consumers of Y.A. fiction, and Green treats his grownup characters with unusual empathy. Hazel worries a good deal about how her death will affect her parents: “There is only one thing in this world shittier than biting it from cancer when you’re sixteen, and that’s having a kid who bites it from cancer.” Green gives Hazel’s mother not only a devoted temperament but a sense of humor; she watches “America’s Next Top Model” with her daughter and takes her to Amsterdam to meet her favorite author, Peter Van Houten. Green’s books seem calibrated for an era in which parents—vigilant and eager not to seem out of touch—often read the books that their children are reading. Lizzie Skurnick, who runs a publishing imprint that reissues Y.A. literature from the past, told me that “Green writes books that are appropriate for teen-agers and for the adults who want books to be appropriate for teen-agers.” Such parents may be pleased that their child is touched enough by a book to cry over it, but they don’t want the experience to be too unsettling. Skurnick feels that Green’s approach is a bit tamer than that of Y.A. authors from earlier eras: Judy Blume, Lois Lowry, Richard Peck. In Katherine Paterson’s beloved 1977 book, “Bridge to Terabithia,” a fifth grader’s best friend dies alone in the woods after falling from a rope swing, and there is little consolation in the form of either teachable ideas or romantic spark. “John Green’s books all have a point and a lesson,” Skurnick said. “They’re sophisticated points, but they’re there.”

In April, I visited Green in Indianapolis. He has lived there since 2007, when Sarah took a curatorial position at the Indianapolis Museum of Art. In the Midwest, the Greens added to their household, in this order: Willy, a West Highland terrier; Henry, their now four-year-old son; and Alice, their daughter, who just turned one. When Sarah was pregnant with Alice, the Greens did a Google Hangout with Barack Obama, during which they asked him which name he preferred: Eleanor or Alice. The President demurred, saying, “The main thing is, tell either Eleanor or Alice not to forget to be awesome.” I was staying downtown, and Green picked me up in his car, a Chevy Volt, to take me to his office and video-production studio, in the Broad Ripple neighborhood. He was wearing a checked shirt, jeans, and Adidas sneakers with green-and-turquoise Argyle socks. At one point, he told me, “I don’t see why anyone would ever wear socks that are not Argyle.” Broad Ripple is as cute as its name. There are coffeehouses tucked into bright-painted wooden buildings and brewpubs in older brick ones. Green’s office occupies the third floor of a solid, Midwestern-looking building. Nearby, there’s an encampment of youngish homeless people, known locally as the Bridge Kids, and a weekly farmers’ market that makes an appearance in “Stars.” At work, Green has surrounded himself with people who are approximately as smart as he is, but a lot calmer. When I asked Sarah how anxious John was, she laughed and said, “The word ‘very’ comes to mind.” But, she said, “it’s part of his identity and the way he experiences the world, and it’s not a wholly inward-focussed anxiety. It also helps him to be empathetic.” Green told me that he had been prone to “obsessive thought spirals for as long as I could remember”—but he’d had good therapy, starting when he was a teen-ager, and felt that his emotions were “fairly well managed.” Besides, “from a novelist’s perspective, the ability to cycle through all the possibilities and choose the worst is very helpful.” Vlogbrothers, which has more than two million subscribers, has become the anchor of an online empire. In 2011, after YouTube approached the Greens about doing additional series, they launched Crash Course videos—short educational lectures with animation accompaniments. John handles the humanities, Hank the sciences. The videos, which have the jump-cut aesthetic and speedy delivery of the Vlogbrothers posts, are the pedagogical equivalent of Red Bull shots, and if you watched them all you’d know a lot, but you’d also think you knew more than you did. Raoul Meyer, a history teacher who taught John Green in high school, and who now writes scripts for Crash Course, is sometimes bothered when people say that John is the best teacher they’ve ever had, because in real life teachers tell you when you’re wrong. “This is delivery of content and we do a really good job of it, but that’s just one part of teaching,” he said. The walls of Green’s office are covered with framed nerdfighter-themed art work, most of which has been thrust into his hands at book signings. In one corner is an Aero Fighters arcade console, a birthday gift from Hank to John. Another gift from Hank hangs on a nearby wall: a photographic mosaic, amassed from hundreds of images of fans, of the “nerdfighter salute,” a gesture in which the hands are crossed at the wrists in a way that makes actual fighting impossible. A video blog may not sound like an intimate medium, but it has brought John and Hank closer. After the first year of Vlogbrothers, they resumed other forms of communication; John told me that they now talk on the phone every day. “If anything, we talk to each other too often,” he said. “Now our collaboration is so deep, and our work together feels so intertwined, that I can’t imagine we were ever so distant. But we still need projects. We still don’t talk about personal stuff.” They say “I love you” once a year—on Esther Day, which is a holiday that Esther Earl asked nerdfighters to observe on her birthday. Her idea was that it could become a celebration of non-romantic love—a day when you’d say “I love you” to people who don’t often hear it from you. “Oh, and Happy Father’s Day.” John walked me into his inner sanctum, where a grubby, oatmeal-colored La-Z-Boy hulked in a corner. “I know it’s not a physically beautiful item,” he said. But his mother gave it to him for his twenty-second birthday, and he has written parts of all his books in it. “It has moved successively farther from the center of our house,” he observed. “In New York, it was dead in the middle of the apartment.” A bookshelf held translated editions of his books. The Norwegian edition of “Stars” is called “Fuck Fate.” Green laughed. “That is, arguably, a better title than ‘The Fault in Our Stars,’ ” he said. “You’ve got to love Norway—you can put ‘fuck’ on the cover of a young-adult book!” That morning, Green was making a Crash Course video about “Beloved,” the Toni Morrison novel. Unlike his Vlogbrothers posts, Green’s Crash Course videos are written not by him but by hired experts. He revises them, however, and as he read the script on a teleprompter he added jokes and asides. The video was being filmed by Stan Muller, a tall, broad-shouldered guy who answered a Craigslist ad placed by Green three years ago. Muller adopted the role of fond, soothing parent. Green reveres “Beloved,” but it’s harrowing—Sethe, a runaway slave, kills her baby—and he was worried about getting the tone right. In Crash Course videos, Green often performs as Me from the Past, a jaded younger version of himself who asks obvious questions. In the guise of this alter ego, Green slouched in a chair and said into the camera, “Like, do you think Beloved is a ghost or not?” As his current self, he complained, “You’re ruining it, Me from the Past. We were having a moment there.” They stopped filming for a second, and Green said, hopefully, “That was kind of a joke. It was almost a joke. It’s about to get really unfunny, though.” One of his knees was jiggling. “Oh, man! How about if I add, ‘You have a special gift for finding the least interesting question’? Can I say that, or is it too dismissive of a large body of scholarship? I don’t care—I think it’s funny. Stan, do you like it?” “I do,” Muller said. “It is the least interesting question you can ask.” “I agree.” Nerdfighters have a term for assessing the heights that Green’s hair achieves when he worriedly tugs on it—“puff levels”—and this morning they were rising. “Fuck, it’s literally haunting, this book,” he said. “Like there’s a ghost in the room.” It was a little surprising to hear Green use “fuck” so often, because he is careful not to do so in his videos or his books. He continued reading the script, evoking the book’s themes of dehumanization, buried memory, and love that’s “too thick.” He then described the moment when Sethe, caught by her slave-owner, takes her kids “out back to the woodshed to kill them all before he can take them.” In an unusually slow voice, he noted, “She only manages to kill one, sawing through its neck.” Afterward, he worried some more: “Gaaaaah. This is going to get, like, the least views of any Crash Course video ever made.” “Nah,” Muller replied. “It’ll get a hundred thousand.”

Afterward, in Green’s office, we talked about the years of his life that might be chronicled in a Y.A. novel. He grew up in Orlando, Florida, where his father, Mike, was the state director of the Nature Conservancy; his mother, Sydney, stayed home with John and Hank when they were little, then worked for a local nonprofit called the Healthy Community Initiative. Green’s parents now live near Asheville, North Carolina. “They have goats and chickens and a vegetable garden and make goat’s-milk soap,” Green said. “I was so worried about them leaving their home of twenty-five years and, like, an hour after they arrived they were the happiest they’d ever been.” In middle school, Green said, he was a regrettable combination: a nerd who was not a good student. He was also bullied and unhappy. When he was fifteen, his parents sent him to Indian Springs, a boarding school outside Birmingham, Alabama. It was an excellent move. Green had always loved to read—he had a soft spot for “girl books,” like the Baby-Sitters Club series—but in high school he read Salinger, Vonnegut, Morrison, and Chabon, and found other people who liked to talk about books. Indian Springs offered the kind of verdant, self-contained setting where one could have a preëmptively nostalgic coming-of-age. You could almost feel yourself missing it while you were still there. Green captures this delicious melancholy in “Looking for Alaska,” which tells a story of friendship, first love, and intellectual questing at a school very much like Indian Springs. Green was much happier in Alabama, but he remained a “genuinely poor student.” He told me, “I had always been told I was smart and had potential, but I had never shown the ability to deliver on it. It’s a bit cliché to say, but I think I actually was scared I wasn’t smart.” (After a beat: “I was actively bad at math. And languages.”) Raoul Meyer, then a young teacher at Indian Springs, has a different take. He told me, “John was very vocal about his relationships with his friends being more important than his schoolwork. He broke a lot of rules—he smoked very visibly, for instance, and frequently got caught. You had the impression that if he’d wanted to be an A student he could have been, but that wasn’t the identity he wanted.” The writer Daniel Alarcón was in Green’s class, and remembers that they both wanted to be writers then, and “shared a seriousness about it that wasn’t exactly normal for adolescents.” Not until Alarcón enrolled in the M.F.A. program at Iowa was he again around people who, like Green, “talked about literature the way other people talked about sports, and who could break down a story over beer and not think of it as pretentious or boring.” Alarcón recalled a road trip to Orlando that he took with Green and Townsend Kyser, the scion of a catfish-farming family. Once there, they “spent, like, a week writing oblique and inscrutable messages on construction paper and planting them in public places, like the manicured lawns of branch banks.” At Indian Springs, Green also became friends with boarders who staged brazen pranks. In one infamous episode, someone invited a woman who was supposedly an academic expert on teen sexuality to speak at an assembly; in fact, she was a stripper, and started disrobing in response to the urging of a guy in the audience. In “Looking for Alaska,” a similar incident occurs, but the stripper is a man, the student in the audience is a young woman, and the whole stunt is an homage to a troubled girl who has died in a car accident—all of which makes it far more palatable. When Green was at Indian Springs, a girl at the school was killed in a car accident. She wasn’t a close friend, but it was a small school, and, as he said, “it’s so hard to get your head around that when you’re a kid.” He went on, “Infinite sets are a difficult thing to get your head around generally, but the forever of it—I just felt so bad for her. I still feel so bad for her.” Although Green often suggests that he was a sad-sack dork as a teen-ager, his old friends don’t remember him that way. Alarcón said, “At our school, we didn’t really have jocks. It was a pretty high-achieving school. I’m not saying it was paradise. Plenty of kids are socially awkward, and there’s nothing that will save them from other adolescents. But John wasn’t like that at all. John was funny and charming, and people looked up to him.” Green was sensitive, and he fell hard for the girls he had crushes on, but Alarcón said that “John exaggerates his haplessness with women,” adding, “This is just speculation, but if your fans are a lot of thirteen-to-fifteen-year-old girls, it seems kind of smarmy if you come across like a ladies’ man.” Green enrolled in Kenyon in 1995. He chose a double major in religion and literature. His friend Kathy Hickner, who also hung out in the religion department, remembers him as “one of these really huge personalities” who was “always talking,” but also as the person she could count on “to go to church with me and discuss the sermon.” She added, “We were both into this whole layer of Christian thinkers who were very open-minded, scholarly types.” Green continued to pursue writing, particularly in an evening seminar that he took with the novelist P. F. Kluge, who was, Green recalled, “encouraging of my work but also very, very critical of it—I once titled a story ‘Things Remembered, Things Forgotten,’ and he said, ‘Green, you don’t get to title your stories anymore.’ ” When Green was not accepted into the advanced creative-writing course at Kenyon, “it was crushing,” he recalled. “Kluge took me to his house and poured me a drink and said, ‘I think you should have gotten into the class. But your writing isn’t that great.’ I think he called it a ‘solid B-plus.’ But, he said, ‘the stories that you tell during the smoke break—if you could write the way you told those stories, then you would write well.’ ” Kluge told me that what he remembered most about Green was not his writing but his “spoken energy.” “He was so rapid-fire,” he said. “Also decent, self-deprecating, and funny.” In class one evening, Green read aloud a story with a sex scene in it. When he was done, the other students offered polite critiques. Kluge then said, “Green, you’ve never had sex before, have you?” Green said no. In subsequent classes, he provided updates on the status of his virginity, which for a long time was “nothing new to report.” Upon graduating, he moved to Chicago, where he eventually ended up at Booklist. He was hired to do data entry, but he found mentors in the editor-in-chief, Bill Ott, and Ilene Cooper, a staff editor who also wrote children’s and young-adult books. Cooper said of Green, “He was a horrible slob, and he didn’t do his job all that well,” recalling that he failed to send out checks to freelancers. “He was smoking but trying to quit, so he was chewing tobacco, which was kind of gross. But he was so engaging, and he would want to talk about things like our place in the universe.” Green’s older colleagues chided him for what Ott called “some of his outrageous young-person pronouncements,” such as the claim that black-and-white movies are a waste of time. Ott said that he and Cooper, who are now married, saw him through a “ ‘Sorrows of Young Werther’-like downturn” after a girlfriend dumped him; Green told me that Ott ordered him to watch the profoundly silly 1950 film “Harvey,” which both lifted his spirits and cured him of his antipathy toward black-and-white. Eventually, Ott started assigning Green reviews, and Cooper did several edits on the manuscript of “Looking for Alaska,” which she passed along to her publisher, Dutton. When Green was twenty-six, he met Sarah Urist, who was managing an art gallery in Chicago. She had been three years behind him at Indian Springs, and they became reacquainted through the woman Green was then dating—Sarah’s sparring partner at a boxing gym. After Green and the girlfriend broke up, he and Sarah started a friendship with a large epistolary component. “We e-mailed back and forth for a year and talked about everything,” Green said. “It was one of the most invigorating conversations I can remember having.” When I met Sarah, she was wearing red lipstick, black boots, and tortoiseshell glasses; she is at once hipper than Green—she’s grounded in theory and cutting-edge art—and steadier, with a quieter, more skeptical sense of humor. She left her job at the Indianapolis museum last fall, and now works with Green on a Web series called “The Art Assignment,” in which she showcases contemporary artists who then “assign” viewers to make a specific work of art. Sarah told me that she had an intellectual interest in fandoms like her husband’s, but found them difficult to identify with. “It’s a bias I have to get over, because being a fan is so much a part of young life now,” she said. “But there’s part of me that’s always wondering, How much could you really love all of these things?”

One of the themes of “The Fault in Our Stars” is the relationship between authors and readers. Hazel says, “Sometimes, you read a book and it fills you with this weird evangelical zeal, and you become convinced that the shattered world will never be put back together unless and until all living humans read the book. And then there are books like ‘An Imperial Affliction’ ”—Peter Van Houten’s novel—“which you can’t tell people about, books so special and rare and yours that advertising your affection feels like a betrayal.” In a different era, “The Fault in Our Stars” could have been that kind of cultish book. For many young people today, however, reading is not an act of private communion with an author whom they imagine vaguely, if at all, but a prelude to a social experience—following the author on Twitter, meeting other readers, collaborating with them on projects, writing fan fiction. In our connected age, even books have become interactive phenomena. Green, for his part, seems to feel that it is a betrayal not to advertise your affections. Every day, he gives his fans a live stream of his stream of consciousness. In addition to posting on YouTube, Green contributes indefatigably to Tumblr and Twitter. Even when he’s feeling anxious, he’s willing to chat with people who approach him in public. As his fame has grown, he has discovered the need for a few limits: he doesn’t like it when fans show up at his house or make Tumblrs about his kids. Green’s boyishness and his energy make a lot of what he does look easy. But it’s hard for him to channel the emotional kid inside while remaining an analytical adult—to embrace simultaneously the voluble aesthetic of the Internet and the contemplative sensibility of the novelist. Raoul Meyer, the history teacher, told me, “John strikes me in some ways as the same teen-ager he once was, just trying to figure out his place in the world. Only now the world is changing much faster and he’s an agent of that change, creating the world he’s trying to fit into. And that’s a tough role.” Green’s online projects keep proliferating along with his fans, and he seems determined to keep up with them all. He told me that he has sketched out some scenes for a new novel, about “two male best friends who live less privileged lives in a world of privilege,” and that he hopes to work on it after the movie junkets are over and he has taken a few days of vacation with his family, in a Tennessee farmhouse devoid of electronic devices. One wonders, however, when he’ll actually find the hours to recline in the La-Z-Boy. E. Lockhart, an acclaimed Y.A. novelist, is an old friend of Green’s. She said, “Most of us look at what John does and say ‘That’s awesome,’ but we’d rather be in our pajamas writing.”