text: [Themes: sci-fi, mystery, science fiction]
  
  By the time the Orion enters orbit around the planet Folvan on the fifth day, you and your team are gearing up for your expedition. You change into your field uniforms and load a variety of supplies onto your assigned shuttlecraft. Then when the bridge gives you clearance to depart, you all board the shuttle and fly off into space.
  
  Only now do you get your first real look at Folvan: a large, drab-green world with no discernible continents, and with only one of its isolated oceans currently in view. The surface is otherwise one continuous landmass, with a cluster of large lakes scattered across a portion of the northern hemisphere.
  
  Earlier today, on your way to the Orion's flight deck, Hun-Spruk confided with you that she had spent almost all of her free time since the mission briefing studying Dr. Munro's reports from the last four years.
  
  "She says the Folvans are a vegetarian race," Hun-Spruk said, "but she suspects their evolutionary ancestors developed sentience as a means to avoid the planet's apex predators, some of which can attack by air. By forming complex social groups and constructing better shelters, the Folvans have beaten the odds and managed to survive in a harsh environment."
  
  Her enthusiasm for the mission--and for Dr. Munro's work in particular--was obvious. "I tried to read the doctor's reports," you said, "but I had a hard time getting through them."
  
  "To be honest," she said, "Lori Munro has always been one of my heroes."
  
  Now your science officer is manning the shuttle's sensor station as you make the final approach to the planet. "I'm not detecting any human life signs," Hun-Spruk says. The craft is starting to vibrate as it enters the upper atmosphere. "I started with the crater in the northern hemisphere where Dr. Munro is basing her research, but when I detected nothing there I scanned a much larger area. Still nothing."
  
  "That's not good," you say. There should be four humans down there: Dr. Munro, Ander Dyo, and the two assistants. "Ask the Orion to scan the entire surface of the planet. Maybe they've just taken an unannounced trip."
  
  Or perhaps that is just you being optimistic.
  
  A moment later your science officer relays the message from the Orion's bridge: no human biosigns can be detected anywhere on Folvan.
  
  "Well I guess this is about more than just a malfunctioning comm unit," Dansmith says dryly. But for you the implications are unpleasant to consider: are the researchers dead, or were they somehow removed from the planet?
  
  "There is another possibility," Hun-Spruk says after a moment of thought. "These crater valleys are laced with heavy amounts of iron, perhaps from the asteroid impacts that devastated the planet's ecosystem millennia ago. The iron could easily be interfering with our scans."
  
  "Wouldn't that interference be localized, though?" you ask.
  
  "Normally, maybe. But look at this." She is pointing to a holographic map, and particularly to a rather large and ancient impact crater with a semi-circular ridge of mountains on one side and a large lake on the other. The lake occupies the remains of several smaller interlocking craters, creating a giant blue snowman shape on the planet's surface.
  
  "See? It's not just one crater, but an entire series of them," she explains. "The asteroid broke up in the atmosphere and made multiple impacts. It left traces of itself over a region 150 kilometers in diameter."
  
  "So you mean we'll be in the dark, as far as our sensors go?" Dansmith asks.
  
  "Yes, it looks that way."
  
  "Where do you want to set down, Lieutenant?" the shuttle pilot asks. He is a no-nonsense Warrant Officer named Galin Hinju, an artist with the holo-virtual controls; by moving his upper body he can direct the movement of the shuttle. Judging by the ornate tattoos covering every visible portion of his body, you suspect that he hails from one of the coastal settlements along the planet Kaitoo's singular ocean.
  
  "My instructions are to set you down somewhere near Dr. Munro's last known location, but far enough from the native population to avoid being seen," Hinju explains.
  
  "As I see it we have three options," Hun-Spruk says. "The research team maintains three blinds in the vicinity of the largest crater, here." Again she points to the holographic map, and in particular an area at the southwest corner of the lake.
  
  "One station is located near a native village on the shore of Lake Syack," she says. "But because of the risk involved in accessing a site so close to the Folvans, they rarely go there."
  
  As she peruses the map, you notice there is no sign of her previous shyness; her enthusiasm is on display for all to see. Clearly, she has done a lot of research in preparation for this expedition and is prepared to assume the role of the mission's subject matter expert. Lieutenant Hun-Spruk is not particularly tall, and you wonder how she'll do if at any point you are forced to wade out through the tall prairie vegetation. But there is no reason to doubt either her commitment or her knowledge. You decide that you'll have to tap her expertise frequently during the course of this mission.
  
  "The main research station is way out here on this uninhabited prairie," Hun-Spruk continues. "But according to Dr. Munro's reports, the preferred observation post is this small one way up here in these mountains, above the village. Much of their data has come from here. I think either of these two sites would be a good place to start looking for our people."
  
  Hinju, who has been following along even while piloting the shuttle, points out, "I'm not sure we can land anywhere on the open prairie and remain unseen, but those mountains will provide good cover."
  
  > If you land at the main research post out on the open prairie, turn to page 48.
  "It makes the most sense to check out the main post first," you say.
  
  "I agree," Hun-Spruk says. "This was for a while the team's primary living quarters, so if we're going to find any clues to their disappearance, this very well could be the place."
  
  It is very early in the morning on this side of Folvan, still very dark, and Hinju flies the shuttle in a wide arc that comes nowhere near the native village by the lake. He drops down so low over the prairie that you can see the blades of grass just a few meters below you, illuminated only by the blood-red moonlight of Folvan's only moon. Then he lands in what appears to be the middle of nowhere--a nondescript site in the grasslands about ten kilometers south of the Folvan village.
  
  You pick up your backpack, surprised by how heavy it has become; a moment ago it weighed only a few kilos, but now because of the stronger gravity it feels as though someone placed a large rock inside. The shuttle's hatch opens, and you descend the steps to the ground.
  
  With the aid of her WristComp, Lieutenant Hun-Spruk finds the hidden entrance to the research post and opens it. With Hinju watching from the bottom of the steps to the shuttle, you follow the rest of your team into the research post, which was dug into the ground much like a bunker. With the entrance closed there is almost no sign of it, but once inside you find a spacious structure where four people live and work.
  
  > Page 12
  Except that when Chief Dansmith gets the lights to work, you can see the place is a wreck. Materials are strewn everywhere, and it appears some of the furniture been chewed apart by wild animals.
  
  "I don't think this place has been lived in for months," Dansmith says. "I see no signs of a struggle, no half-eaten meals, nothing to suggest the research team left in a hurry. The place is just... abandoned."
  
  "But that doesn't make sense," Hun-Spruk says. "Up until we lost contact with Dr. Munro two weeks ago, she never indicated that anything was out of the ordinary. It wasn't until she stopped sending messages to Star Base Ishtria that we had any idea there was something wrong."
  
  "That may be," Dr. Wildon says, "but I agree with the assessment that no one has lived here for quite a long time."
  
  There is a pause when no one can think of what to say next, because of the implications of what you've just concluded: either Dr. Munro was deliberately sending false reports, or many of her transmissions were fabricated by someone else. Either way, this is turning out to be no mere search and rescue operation.
  
  "Is that datapad over there functional?" you ask. You point to the computer tablet on a table in the middle of the room.
  
  "Maybe," Dansmith says. "Let me take a look at it." He pulls out a chair, dusts off the seat, and sits down at the table to examine the pad.
  
  > Page 13
  Rather than watch your technical expert tinker away--the small device seemingly overmatched by his powerful arms--you busy yourself by peering into the handful of smaller rooms to the side of the main work area. Something clatters in the corner of the rightmost room, where the door is ajar and you can just make out a stool in the shadow. The main light doesn't reach in there, and you see no easy way to activate the diode panel inside, so you reach for the handlight stowed in the pocket of your field jacket and point the beam into the darkness.
  
  Two eyes reflect the light beam back to you.
  
  "I found something," you say. Hun-Spruk turns to see what you see, and a small creature scurries deeper into the darkness. You both follow it with your handlights. For a moment you can see it clearly: about a meter tall, somewhat like a primate but with ears like an Earth rabbit, and long, thick fingers culminating in blade-like nails.
  
  "It's a passafan," she says. "Nocturnal creatures."
  
  "Dangerous?" you say.
  
  "Only if you're a plant root or a tuber," she says.
  
  In a flash the passafan is gone, running underneath a work desk in the corner and disappearing into a large hole in the wall. The opening is big enough that you could easily crawl inside, making you wonder what else might be hidden behind the wall. But do you really want to risk cornering a wild animal in its den, if that's what the hole leads to?
  
  > If you follow the passafan, turn to page 10.
  "This could be fun," you say, just before pulling the desk away from the wall so that you can get a better look at the space into which the passafan disappeared.
  
  The wall is just a thin chipboard panel--a structural formality intended to keep the earth surrounding this bunker from collapsing into the living space. The edges of the hole have tooth marks, telling you that it was gnawed into existence. Certainly, this passage must lead to some kind of secret realm of the passafans, you think.
  
  Hun-Spruk kneels down to examine the opening, shining her handlight inside. "Is our passafan friend in there?" you ask.
  
  "You know what?" she says. "This is no animal den. There is a tunnel of some kind back there."
  
  She stands up and starts feeling around the remaining portion of the wall panel above the hole, and not finding what she's looking for, she starts to tug on the edge of the hole more aggressively. "Can you help me?" she asks, and together you rip the panel off the studs.
  
  "It's a passageway for sure," you say, shining your handlight through the large opening you've just uncovered. There is no sign of the passafan, or anything else--just a long tunnel leading straight ahead into the darkness.
  
  "All right, I've got to scan this," Hun-Spruk says, and she holds up her left arm and points her WristComp into the tunnel. You watch as a holographic map is rendered before your eyes, depicting a tunnel several hundred meters long.
  
  > Page 67
  "There you two are."
  
  You turn and see Dr. Wildon standing in the doorway, back-lit by the light from the main room. "My my, what have we here?" he says.
  
  "Damned if we knew," Hun-Spruk says. "We thought we were about to discover a passafan den, but we found this tunnel instead."
  
  "Well I guess this place is more interesting than we first thought," Dr. Wildon says. "So I suppose you two are itching to go explore this thing?"
  
  Actually, you're not so sure about that. "Want to join us?" you say, secretly hoping that maybe he'll volunteer to go instead of you.
  
  "Me? No," he says. "But I'll let everyone know where you've gone, and make sure no one leaves without you."
  
  "Much appreciated," you say, in reality feeling distinctly disappointed.
  
  When he leaves the room, you turn to Hun-Spruk. "You found this tunnel, so I'll let you go first."
  
  With her WristComp pointed forward on her left arm, and a handlight in her right palm, your science officer steps into the tunnel. She actually seems highly curious to explore this dark and narrow space, much to your dismay. Despite your better judgment, you follow close behind.
  
  "Any idea how far this thing goes?" you ask.
  
  "No. The soil here is laced with heavy amounts of iron, and it's interfering with my scans."
  
  You touch the wall, expecting to feel dry soil, but instead the tunnel is lined with what feels like clay. The tunnel angles downward at a slight pitch. Hun-Spruk's WristComp continues mapping the tunnel ahead of you as you go, scanning as far as it can given the iron-laden soil, but so far it is revealing a single shaft leading in a single direction, with no turns or deviations from its course.
  
  "This could go on forever as far as we know," you say.
  
  > Page 68
  "So this is interesting," Hun-Spruk says. "We're heading toward Folvan's magnetic north pole."
  
  "Isn't the native village north of here?" you say.
  
  "Exactly. It's as if this tunnel is the underground expressway between the village and the research post," she says.
  
  "Well, Dr. Munro did have another research post just outside the village," you say. "Maybe this was her secret route between the two, so she could travel back and forth at will without being seen."
  
  "That makes sense," Hun-Spruk says. "It's just odd that she never mentioned this in her reports to Star Base Ishtria before."
  
  It feels very unsettling to be in such a dark space, with no light but the ones you carry, and with walls so close that even the sound of your breathing has a slight echo. Hun-Spruk, on the other hand, seems to be unfazed.
  
  "How far below the surface are we? Ten meters?" you ask.
  
  "Just five. Notice that we've leveled off," she says.
  
  "So here's my thinking," you say, doing your best to sound calm, controlled, and reasonable. "If this does lead to the next research post, we shouldn't go there without the others. So let's head back and see how Chief Dansmith is doing with the datapad, and we can decide what to do from there."
  
  "Don't tell me you're getting claustrophobic, Lieutenant," Hun-Spruk says. "We've only gone 300 meters. Let me map at least the first kilometer before we head back."
  
  > If you insist on heading back to the main research post now, turn to page 39.
  You don't even wait for Hun-Spruk to respond; you're out of your element in this tunnel, and you need to get out. You never should have entered this thing in the first place. Even with the handlights it is very dark in here, and you can envision many different ways in which things could go wrong: the dirt ceiling may collapse on you, the passafans may react aggressively if you stumble into one of their dens, your handlights may die and leave you in the pitch-black darkness.
  
  You hear Hun-Spruk behind you. "Lieutenant?" she says. "Are you all right?" But you're practically running back toward the tunnel entrance, stumbling over the unevenness of the floor.
  
  You emerge from the tunnel, but the side room is dark too. So it is not until you reach the main room with its diode light panels that you feel like you can stop running. It is as if you had fallen into a deep, dark lake, and were going to drown if you could not surface in time. Only when you reached the light did you feel like you could finally breathe again.
  
  But now your heart is racing, and you're aware that Chief Dansmith and Dr. Wildon are watching you.
  
  "How are you doing, Lieutenant?" the doctor asks.
  
  "I'm fine," you say, a little too abruptly. You try not to make eye contact with him, for fear of what he might see.
  
  "Yeah? Would you like to come and get some fresh air with me?"
  
  To be honest you're not sure quite what you want; you never do when you get like this. But some fresh air might help you collect yourself, so you get up and step outside without saying another word.
  
  > Page 145
  Starman Quabiss, your young security specialist, is standing watch at the entrance to the bunker. He is unaware of what just happened and is about to say something to you, but you just want to avoid people right now--people and their judgment.
  
  You never should have went inside that tunnel. You thought you could control your anxiety, but the combination of the darkness and the confined space got the better of you.
  
  Now you just want to hide in the prairie grass and let this panic attack pass you by. The night air feels good; the fact that you just exposed a personal weakness to the people in your command is a secondary concern right now.
  
  Somehow, you're sure the mission will proceed without your direct involvement for a few minutes.