A plane crash leaves a girl with bug knowledge stranded on an island where insects are the size of buildings, and the show's idea of survival horror is watching what those insects do to human bodies. The gore isn't window dressing, it's the entire point, graphic and sustained in ways most anime won't touch. This is a one-episode commitment to genuine biological horror that doesn't flinch, doesn't cut away, and doesn't care if you're comfortable watching it.
A plane carrying a class of students crashes on an uncharted island, leaving survivors scattered and disoriented. Oribe Mutsumi steps up to lead the group, armed with genuine knowledge of insects and survival tactics. She calculates rescue will arrive within days. Three days should be manageable, right. Then they encounter the island's actual inhabitants: insects the size of buildings. A wasp the height of a person. Beetles that move like armored tanks. What should have been a straightforward rescue operation transforms into a desperate fight for survival against an ecosystem designed to kill them. Mutsumi's encyclopedic knowledge of entomology becomes their only advantage, but knowing an insect's behavior and actually staying alive long enough to use that knowledge are two different things. Her classmates fracture under pressure. Resources dwindle. The insects show no mercy and no pattern that follows normal biology. Each encounter pushes the group closer to panic, closer to death, and closer to the question of whether rescue is even coming at all.