Anna, Javi, and Molly, tied together with bungee cords, jump through the treetops using the gravity device. They call for Yoshi but get no response. After a brief discussion about how the physics of mass versus weight is affecting their long jumps and ability to push off the treetops, they spot a perfect circle of unnaturally tall trees. A large flock of shredder birds emerges from the strange trees and attacks. Molly uses a flare, which only partially deters the birds. To evade them, Anna toggles the gravity device on and off, causing the team to drop suddenly through the canopy. The birds, attracted to the device, overshoot them. Anna gets tangled in a tree and must turn the device off completely, leaving her clinging to the trunk as the birds scatter. She concludes that the device and the jungle’s creatures really are connected.

Deciding that treetop travel is too dangerous, the team proceeds on foot toward the waterfall. On the way, Javi admires blue glowing bugs that fly around and considers collecting them in a jar in case their light comes in handy. They arrive at the clearing and find Yoshi’s shirt neatly laid out to dry. Javi and Molly step onto a bed of red vines to investigate and discover small animal skeletons. The vines suddenly attack, wrapping around their limbs. Javi tries to use a flare, but a vine snatches it away before he can ignite it. Just as they’re about to be overpowered, Yoshi appears. He uses his katana to slice through the vines, freeing the teens. He’s named the predatory plant “tanglevine.”

The reunited group makes camp for the night, building a fire for protection. As Yoshi cleans his 400-year-old katana, which is prone to rust because it was made before the discovery of stainless steel, the team discusses their bizarre situation. Anna proposes a theory that the device is casting a kind of “gravity shadow” away from the group. Yoshi offers a different idea: They’re on a spaceship with artificial gravity, and the device is merely a remote control. He supports his theory with the radio transmission he heard near the waterfall. Molly, refusing to believe they’re in space, proposes an experiment to prove that they’re still on Earth. With the others’ help, she uses the gravity device to launch herself high above the jungle mist. She sees a sky full of stars but also two moons—one red and one green. Her conclusion is that the plane has somehow been transported to another planet.

Yoshi wakes to find Molly staring at the two moons, which are now visible from the ground since the mist has thinned. She heard a loud, foghorn-like cry from a large creature during the night. Yoshi takes over the watch and, just before dawn, also hears a large animal moving through the jungle. The next day, the group travels back toward the plane, following a stream. They’re attacked again by shredder birds and escape by dropping into the water. Nearby, they discover a tree with massive claw marks gouged into the trunk. Soon after, they spot the plane’s wreckage trail and head back to camp.

The group returns to the plane, where Caleb confronts them for leaving. Anna explains their discoveries, including the fact that they’re on another planet, which Caleb dismisses. To find a sustainable food source, Anna devises a systematic test for the local berries. All seven survivors—Molly, Javi, Anna, Yoshi, Oliver, Kira, and Akiko—agree to participate in a random drawing to determine who will be the first to taste a batch of green berries. Kira draws the first marked straw.

As the others argue that Kira is too young to test the potentially poisonous berries, Javi impulsively eats them himself. The berries taste horrible, and he immediately becomes violently ill, vomiting everything in his stomach. Anna realizes that the green berries act as a powerful emetic, which could be useful. Javi names them “pukeberries.” Kira then tries a handful of red berries, which she finds omoshiroi, or “interesting” in Japanese. Yoshi eats the blue berries and declares them delicious. Anna cautions them to wait a few hours to ensure that there are no delayed toxic effects.

While waiting to see if the berries have any ill effects, Kira sketches Yoshi. Yoshi grows impatient, wanting to return to the waterfall to investigate the radio signal. While Akiko plays a flute, she attracts a “slide-whistle bird” (129). Seeing an opportunity to hunt, Yoshi kills the bird with his sword, upsetting Akiko. He realizes that the others are too cautious to explore and resolves to go off alone again, even if it means stealing the gravity device. He prepares to cook the bird over Caleb’s signal fire.

After eating the delicious roasted bird, which pairs perfectly with the “omoshiroi-berries,” the group fails to catch another. Oliver confronts the older survivors for avoiding the truth about the fate of the other passengers and their teacher, Mr. Keating. Oliver forces everyone to admit that all the other passengers are most likely dead. This prompts the members of Team Killbot to share memories of Mr. Keating and grieve together. To settle the debate about their location, Caleb reveals that he’s an amateur astronomer and proposes a plan: He agrees to be launched above the mist to observe the stars. In return, the others must help him build up his signal fire.

The group uses the gravity device to help Caleb build a massive bonfire. Once it’s roaring, they prepare to launch him into the sky, giving him a flare for emergencies. Just after he ascends, a sudden cold wind kicks up. They see Caleb’s flare ignite far off course, showing that he’s been blown away. The flare then falls and vanishes into the jungle. As they watch, a deep, foghorn-like cry echoes through the night.

Launched above the mist, Caleb sees the stars and two moons. He determines that the moons must be fake because their misaligned phases are physically impossible. Suddenly, a strong wind blows him far from the camp. As he jumps through the treetops to get back, he notices a perfectly circular patch of darkness in the jungle. He decides to investigate. As he flies over the circle, the gravity device buzzes and shuts off, and Caleb plummets into the darkness below.

The group sees Caleb’s flare suddenly drop from the sky into a dark patch of jungle. Worried that he’s hurt, Molly leads a rescue party. As they approach the area, they feel strange ripples of low gravity and hear what sounds like a person groaning. They discover a sharply defined circular zone where the trees are gnarled and there are no “glowflies”—the name that Javi gave the blue glowing bugs. When Javi steps across the boundary, he’s crushed by what feels like double gravity. Molly follows and also struggles. They realize that the area has a high-gravity field. Anna, Yoshi, and Kira circle the boundary and find Caleb lying inside, calling for help.

Javi and Molly are dragged out of the high-gravity zone. Caleb is inside the field, fatally injured from his fall. The gravity device lies beside him, emitting weak pulses of low gravity as it fights the intense field. With his last breaths, Caleb tells them that the moons are fake and tries to say a final word that sounds like “Urss” before he dies. As a cold rain begins, the group retreats to find shelter, leaving Caleb’s body behind. Molly blames herself for his death, but Javi comforts her, insisting that Caleb’s final clue will help them understand their situation and survive.