Arachnid

A translucent alien spaceship hovers over the South Pacific. A test stealth plane piloted by Joli Mercer pursues the ship, but the craft begins to malfunction. The plane makes an emergency approach toward a nearby island, where the crew hopes to survive the encounter.

Mercer lands on the island and discovers the spaceship destroyed and its alien pilot. A giant spider emerges from the jungle and attacks him, killing the alien and driving Mercer to flee for his life.

Ten months later, Loren Mercer is hired to pilot a medical expedition organized by Dr. Samuel Leon, with assistant Susana Gabriel. The expedition is led by Lev Valentine and includes Bear, Reyes, arachnologist Henry Capri, Toe Boy, and two native helpers. The team’s mission is to reach the island and investigate the mysterious illness.

Upon arrival, the expedition's plane malfunctions and they are forced to land on the beach. The group begins to set up a base and start preliminary reconnaissance, but ominous signs appear in the environment.

The next morning, strange ticks burrow into Reyes. The group reaches the village only to find it deserted and eerily quiet. Capri notes that insects in the area have mutated, signaling a dangerous ecological shift.

Reyes dies from the tick infestation; Bear mercifully euthanizes him to end his pain. At night, a giant centipede emerges and kills one of the natives, underscoring the island's lethal dangers.

Mercer finds some of her brother Joli's clothing among the gear and confesses to Valentine that she is searching for him. The revelation deepens the personal stakes of the mission for the group.

Valentine announces that they should leave the island the next morning to escape the danger. Mercer and Capri refuse to abandon their search for Joli, creating tension within the team.

The next day Capri leaves the village. Bear is sent with a native to locate a radio signal for help, but on a river journey the native is killed by a small creature. The danger intensifies as the expedition struggles to communicate with the outside world.

Capri locates a dying giant centipede, and a giant spider attacks him. Meanwhile, the others discover Joli's remains stuck in a tree, confirming he is on the island and adding a personal motive to their mission.

Capri is trapped in spider web and bitten. He pleads to be killed and Susana shoots him to end his suffering. The loss adds urgency to the group’s struggle for survival.

The spider reaches the trio and Samuel is killed while trying to fight it, a victim of the creature's ferocity. Mercer and Valentine manage to reach a military bunker and prepare for a more secure defense against the threat.

Inside the bunker, the spider attacks through a window and Valentine is cut by one of its fangs. Mercer shoots the spider in an eye, and it retreats momentarily, buying the group a fragile reprieve.

At night, the spider sneaks through the bunker's roof and the group is forced into a small room. Susana, suffering from claustrophobia, opens the door and is killed with its stinger. The trio escapes through a trapdoor into underground tunnels.

In the tunnels, the spider breeds within a silk cocoon and egg sacs. Bear is killed during the ensuing assault. Mercer uses Toe Boy's vial of black widow poison and Toe Boy's poisoned darts, then Mercer pulls a thread to collapse the web from the ceiling, killing the spider. The survivors push deeper into the jungle to continue their struggle for survival.