Infestation

Cooper arrives late for work and is promptly fired by his boss Maureen for his chronic tardiness and for driving away customers. He is scolded for fooling around in the office and not taking his job seriously. Just after the confrontation, an extremely loud sound shakes the building and he faints.

Cooper awakens a few days later nauseated and weak, cocooned inside his own office. He struggles free and fights a giant beetle-like insect, managing to salvage Maureen from a cocoon nearby. Maureen regains consciousness and learns that Sara is waiting outside the office; they go outside to check on Sara, who lies unconscious in a cocoon in her car.

As Cooper helps Sara out of her cocoon, Maureen is attacked and captured by a large wasp-like creature. Surrounded by other bugs, the group uses Sara's car alarm to distract them and escape to a nearby restaurant to regroup.

At the restaurant, the team revives a clutch of cocooned survivors: Cindy, Hugo, Hugo's father Albert, Leechee, Roger, PJ and a police officer. The newcomers bring skills and hope as the group plans their next move against the insect threat. Tension rises as they realize the hive is a real, growing danger.

PJ, Roger and a police officer choose to flee in Roger's truck despite warnings. They are ambushed by the bugs, resulting in the deaths of PJ, Roger and the officer. Albert is stung, and Cooper barely saves Cindy from being crushed by the runaway truck.

The survivors reach a building rooftop and observe that the bugs hunt by sound rather than sight. They lure a bug into a storage closet using a radio, then milk it to learn its venom. Leechee analyzes the venom and finds sedatives and proteins that affect victims.

With the hive looming and a red gas emission hinting at danger, the group decides to move toward the nearest military airbase for help. Leechee stays behind to continue studying the nest and help revive more victims. The plan is to reach safety while gathering more data on the bugs.

The group arrives at Hugo's house to find Albert's wife dead from natural causes. They press on to Cindy's brother Chad's house, where Chad has mutated into a spider-like creature. Chad attacks and kills Susan, knocks out Sara, and nearly impales Cooper before Hugo and Albert kill Chad.

The group camps for the night at Chad's house and Sara patches up Cooper. Cindy tries to persuade Cooper to desert the group and run away with her, but he remains loyal to Sara. The next day, they decide to head toward Cooper's dad Ethan's bunker for protection and weapons.

On the way to Ethan's house, a squad of flying bugs forces the group to hide under a bridge. Cindy sees Cooper and Sara holding hands and angrily shouts, drawing the bugs toward the group. Albert shoots Cindy to save the others, and Sara is captured by the bugs.

The team reaches Ethan's house, where Albert mutates into a more insect-like monster. Hugo shoots his father to save the group, allowing them to continue their mission. The violence underscores the escalating mutation threat in the hive.

Cooper is captured by another group and locked in a cell in an abandoned police station. There, he meets a Puerto Rican man who reveals he was part of Leechee's group and that the others probably died in the nest explosion. The looming rescue depends on understanding the hive's power dynamics.

The Puerto Rican man unexpectedly mutates into a mutant while Ethan uses the distraction to kill the enemy group and rescue Cooper and Hugo. The group gains a temporary ally in the mutant as they navigate the dangerous facility.

While the others regroup, Sara wakes inside the bug hive and encounters the queen consuming cocooned victims. This discovery sets the stage for a final push to save Sara and everyone else still trapped in the hive.

Ethan, Hugo and Cooper reach the hive and confront the queen. Ethan traps Cooper to a tree and hands him the escape keys, then enters the hive alone. The team defeats the queen with combined efforts, and Cooper detonates the nest's explosives to obliterate the insects inside. The film ends with the trio turning toward the rumbling outside.