text: the road not taken ( fringe ) " the road not taken " is the nineteenth episode of the first season of the american science fiction drama television series fringe . it centers on the death of a young woman ( jennifer ferrin ) , who spontaneously combusts in the middle of a street . the fringe team 's investigation leads them to learn more about the drug trials olivia ( anna torv ) experienced as a child , as well as other revelations . the episode 's story was written by akiva goldsman , while the teleplay was co - written by executive producer jeff pinkner and supervising producer j.r. orci . it was directed by fred toye . the title is based on the robert frost poem of the same name . robert chiappetta and glen whitman , frequent contributors to the series , aided in the episode 's production by " find [ ing ] a new and gruesome way to blow people up , " and rooting its explanation in science . it first aired in the united states on may 5 , 2009 on the fox network . an estimated 9 . 245 million viewers watched the episode , making it the network 's fifth most watched show for the week . " the road not taken " received mostly positive reviews from television critics , with many praising olivia 's visions of the other universe and john noble 's performance . plot the fringe division investigates the case of a woman ( jennifer ferrin ) who " spontaneously combusts " in the middle of a busy new york street . the team discovers that the victim is the subject of a zft experiment to cultivate pyrokinesis . as they investigate , olivia ( anna torv ) experiences " visions " while awake . walter ( john noble ) suggests she is seeing a parallel universe which has branched off from our own . olivia and peter ( joshua jackson ) visit an agoraphobic website designer ( clint howard ) who is apparently aware of william bell , the drug trials , and the coming war , although his credibility comes into question when he believes himself to be a character in the plot of star trek . using information from her visions , olivia tracks down the victim 's twin sister , who only moments before was kidnapped for more zft experimentation . harris ( michael gaston ) is revealed to be responsible for the crimes , and while closing in on him , olivia gets locked in a room with the twin sister , whose unstable pyrokinetic abilities threaten both their lives . with olivia 's guidance , the woman focuses her energy on harris and incinerates him . olivia finds out that the sisters were part of the same nootropic drug trial that she was as a child . she presses walter to reveal why he and william bell were developing " supersoldiers , " but walter only shares that it was for protection against some impending doom that he regrettably cannot recall . meanwhile , walter reveals that the zft manuscript was written by william bell , and that the copy of the manuscript that zft uses is missing a chapter dealing with ethics . he locates the original , but the observer ( michael cerveris ) shows up and takes walter away , cryptically stating : " it is time to go . " nina sharp ( blair brown ) visits broyles ( lance reddick ) to discuss the observer , and is later shot in her hotel by two masked gunmen using a suppressed pistol . production the episode 's teleplay was co - written by supervising producer j.r. orci and executive producer jeff pinkner , based on a story by akiva goldsman . producer frederick e. o. toye served as director . goldsman had joined the series half way through the season by writing and directing the mythology - riddled episode " bad dreams " , and was instrumental in convincing the showrunners to depict more fringe mythology earlier than planned , most notably with the depiction of parallel universes . the title of " the road not taken " is based on the robert frost poem of the same name . new media consultants and scientists robert chiappetta and glen whitman aided in the production of the episode . they had worked on the series throughout the first season , with their role ranging from directly writing episodes to advising the others on scientific concepts . whitman later explained that they " come to us with questions : is this possible ? where can we go with this ? then we go and read the very technical articles , or talk with scientists , and then translate that into the storytelling medium of our show . " for " the road not taken " , he and chiappetta were asked to again " find a new and gruesome way to blow people up , " this time by rooting it in the concept of pyrokinesis . chiappetta explained , " they wanted to have someone spontaneously combust and burn up . so this is where we sort of leaned back into our mythology . " they and the episode writers developed a storyline in which a victim 's childhood experimentation , when they were injected with something , was now " coming back to haunt them . " whitman noted that the concept , like others in the show , was based on real scientific knowledge , " the notion is , some kind of a medical treatment that they were given allowed their brain to command vibrations that would take place . it really is true that essentially what heat is is vibrations of atoms , so if your brain can cause some kind of vibration to take place , eventually you could create enough heat to even create a flame . " pinkner added , " and if you haven 't yet mastered pyrokinesis and the ability to excite molecules that are outside your body , well then your going to excite the ones inside your body and you 're going to blow up , sadly . " for harris ' immolation scene , first unit director gary rake emphasized safety , explaining that " everyone really has to think about what ’ s going on and really focus tonight . this is a quintessential moment where we can ’ t have any mistakes . " everything in the scene was flame retardant , and a special burn unit crew was present . actor michael gaston 's arm , immersed in a special gel , was actually inflamed and then extinguished after filming was cut . then , gaston 's stand - in , stuntman don hewitt , jr , was completely set on fire . hewitt wore the same costume , a wig , a face shield , and was also covered in a flammable gel . it was gaston 's final episode with the series . actress jasika nicole , who plays junior fbi agent astrid farnsworth , described the episode in a may 2009 interview , " it 's about spontaneously combusting . this is the episode i get to get out of the lab . i remember thinking i can 't wait to see what the set 's going to look like and how they will make it look when the spontaneous combusting takes place . and we get there and it 's just smoke on the walls , like a kitchen fire . i thought that was so funny because i thought there were going to be body parts everywhere , like a small explosion . but it 's a really good episode , which leads you into the coolest parts of the finale episode . " cultural references the episode contains many cultural references , which annalee newitz of io9 attributed to the episode 's writers : " it was bound to happen that one day these four would get together and spawn an episode so packed with in - pop culture references that smacking is probably in order . " peter and walter reference the 1984 supernatural comedy film ghostbusters while investigating the opening scene 's case , and later debate the origin of the term pyrokinesis , coined by author stephen king in his 1981 novel firestarter . emmanuel grayson refers to the titular character of the 1982 science fiction film star trek ii : the wrath of khan , as well as romulans and the united federation of planets , when describing government conspiracies to peter and olivia . grayson also believes himself to be mr. spock . this reference is made even more appropriate by the fact that spock 's mother was named amanda grayson . reception ratings " the road not taken " was first broadcast in the united states on may 5 , 2009 on the fox network . it was watched by an estimated 9 . 245 million viewers , making it the network 's fifth most watched show for the week . the episode earned a 4 . 0 / 10 ratings share among adults aged 18 to 49 , meaning that it was seen by 4 . 0 percent of all 18- to 49 - year - olds , and 10 percent of all 18- to 49 - year - olds watching television at the time of broadcast . fox later aired repeats of season one episodes , including " the road not taken " , that featured twitter posts by some of fringe 's cast and producers . reviews the episode received generally positive reviews from television critics . tv squad 's jane boursaw called the episode 's case " an interesting premise " and was pleased that " things are really , really starting to come together in a big way , which is good , considering that the finale is fast approaching " . annalee newitz of io9 declared it to be " one of the most rewarding episodes ever for people who love the show 's mythology , " and found olivia 's universe - hopping ability to be " truly cool " . newitz concluded that " this was a truly awesome episode with a lot of payoff for those of us who have been glued to the set every tuesday night , looking for answers . " the website later listed " the road not taken " as one of the " crucial " episodes new viewers must watch to get into the show . television without pity graded the episode with a a- . noel murray of the a.v. club complimented the episode 's opening scene for providing a succinct synopsis of the season to new viewers who may have been newly discovering the series after watching its lead - in , american idol . though he graded the episode with an a- , murray did however critique its climatic scene for being " clumsily paced and staged " . murray mainly found positive aspects with the episode , explaining , " for a show that started out being a fairly dour procedural with wacky mad - scientist elements , fringe has really worked its way into that fantasy / sci - fi sweet - spot , where its own forward momentum makes the ridiculous look likely and arcane mythology seem well - worth the time to sort through and analyze . " other highlights murray found was noble 's performance , which he considered his " finest moment in the series to date , " and olivia 's visions of the other universe . ign 's ramsey isler rated the episode with a score of 9 . 2 out of 10 . he thought that after a " stereotypical , over - the - top " characterization in past episodes , gaston " stepped up his portrayal " as harris and was " annoying ... in a much more believable way . " isler found the revelation surrounding harris to be " deliciously surprising , " and wrote that the " last twenty minutes of the episode really ramped up the suspense and action . " however , the ign reviewer thought that while the conversation with grayson was an " hilarious homage to leonard nimoy , it seemed completely superfluous in terms of the overall storyline . " isler concluded his review on a positive note by focusing on noble 's performance , calling it " one of the best scenes [ he ] has ever done as walter bishop . it was emotional , believable , and perfectly accurate for a character that has a high level of self - loathing and remorse for what he 's done , and the hopeless frustration of not being able to remember exactly why he did it . "