The Cave

A Soviet-British group begins to excavate an abandoned 13th-century abbey in the Carpathian Mountains. They set dynamite charges, and the floor splits beneath them, dropping the crew to the bottom of a vast cave system. They hear strange rattling sounds in the darkness as they realize they’re far from any exit.

Dr. Nicolai leads a modern excavation at the abbey site and unearths mosaics and a vast underground river. The discovery hints at a hidden ecosystem awaiting study. The team decides to bring specialists to investigate deeper.

Nicolai hires divers led by brothers Jack and Tyler McAllister to descend the river and probe further. The team also includes specialists: Charlie the climber, Briggs the scout, Strode the sonar expert, and Top Buchanan the survival expert. A plan forms to map the cave and assess possible exits.

Briggs is sent ahead to scout along the river corridor. While he communicates with the surface, something appears on the distance and the video feed suddenly crashes. The crew must rely on limited signals and keep moving.

A large creature seizes Strode and drags him off into the darkness. The encounter triggers the water scooter to crash, causing a rock fall that seals part of the tunnel. With their path blocked, the group must pursue another route along the river.

With no rescue team scheduled for 12 days, Jack and Top decide to follow the river downstream, hoping to find a way out. They move cautiously, facing the unknown as the cave walls close in. The surface world seems distant and unreachable.

Jack is seized and scratched by a creature, managing to sever its claw. Kathryn studies the cell structure of the creature and identifies a parasitic mutation that seems to originate from the cave environment. The mutation hints at an evolving ecosystem adapted to darkness.

Nicolai is seen clinging to a cave wall as Tyler signals his position, but a current drags him underwater. A creature drags Nicolai to his death, leaving the survivors shaken. Jack notices tattooed letters on the creature’s hands, hinting at a pattern behind the mutations.

As the scratches take hold, Jack begins mutating with cave-adapted features. The other survivors grapple with the possibility that the entire ecosystem has been altered by the parasite. Kathryn continues to theorize about how the parasite may be driving the evolution.

A winged creature attacks and kills Charlie, demonstrating that the cave's inhabitants are diverse and dangerous. The survivors realize the surface escape hinges on navigating the evolving parasite-led ecosystem. Tension and fear rise within the group.

The group splits as suspicion about Jack’s judgment grows. Alex, Briggs, and Kathryn go their own way, while Top and Tyler stay with Jack to press forward. Trust fades as the team fights for survival amid the mutated threats.

Jack, Top, and Tyler discover a cavern littered with human skeletons and a possible passage out of the cave. The discovery confirms the danger of the cave and hints that others have tried to escape before. They hurry toward the unknown exit while the team’s dynamic continues to crumble.

Bringing the team to the river, Top, Kathryn, Tyler, and Alex sprint toward the passage, but the rebreathers essential for navigation are stolen by the creatures. Alex is killed in the chase, and the four survivors push toward safety in the remaining time. Top, Kathryn, and Tyler eventually escape toward the surface.

Jack sacrifices himself by triggering a cave-in, sealing off the path behind him to allow Top, Kathryn, and Tyler to reach the surface. The plan succeeds, but his fate remains sealed in the darkness. The survivors mourn their fallen ally as they escape.

Tyler and Kathryn meet at a cafe after escaping, where Tyler asks if the mutated Jack could have survived above ground. Kathryn admits she once believed the parasite could not survive outside the cave, but now suspects it may. As she leaves, Kathryn’s eyes reveal the same mutation Jack bore, and she disappears into the crowd.