CHOPPING MALL

Park Plaza Mall has just installed a state-of-the-art security system, including shutters across all exits and three high-tech robots programmed to disable and apprehend thieves using tasers and tranquilizer guns. Allison Parks and Suzie Lynn, co-workers at a pizzeria in the mall, join up with Ferdy Meisel and Greg Wiliams (Suzie's boyfriend) along with their other friends, couples Rick and Linda Stanton, and Mike Brennan and Leslie Todd—for an after-hours party in a furniture store where Mike, Greg, and Ferdy work. Once the mall closes for the night, the two couples begin to have sex, drink, and party inside the furniture store while Allison is set up to watch movies with Ferdy.

Outside, a lightning storm strikes the mall several times and damages the computer controlling Protectors 1, 2 and 3, which malfunction and kill the technicians and a janitor before starting their routine patrol. When Mike goes to purchase cigarettes for Leslie at a vending machine, Protector 1 attacks him and slashes his throat. When Leslie goes to find him, she is chased by Protector 1, which kills her with a laser. The others witness Leslie's death, and barricade themselves in a stock room.

The women attempt to escape through an air vent, but Suzie panics and they exit the vent system into an automotive shop, arming themselves with gasoline and flares. Meanwhile, the men break into a sporting-goods store to arm themselves with firearms. Reunited, the group use a propane tank to seemingly destroy Protector 1. While the men set up the elevator as a booby trap, the killbots ambush the women and ignite Suzie by shooting her gasoline can, burning her alive. Greg unsuccessfully shoots them before Rick drags him away.

The teenagers regroup and rig the elevator trap on Protector 2, destroying it. They then hide in the restaurant where Allison works. Inside, Greg confronts Allison and Linda about leaving the air ducts and exhibits rage due to Suzie's death, pulling his gun on Ferdy when he intercedes on Allison and Linda's behalf. Rick tries to calm him down, and Ferdy suggests destroying the killbots' main control center in hopes of shutting them all down. The group agrees and heads to the control center on the third floor. The robot throws Greg over the railing and he falls to his death.

On the run, the four remaining survivors, Allison, Ferdy, Rick, and Linda also find the first Protector robot recovered after its earlier defeat. They take refuge inside a department store and set up mannequins to confuse Protector 1 and Protector 3. Their plan works, as the robots fire at the dummies and one of them blinds itself with its own reflected laser. However, the blind Protector 3 kills Linda, and an enraged Rick rams a golf cart into it. A bolt of electricity kills him, but his attack succeeds in destroying the third Protector robot.

Protector 1 corners Allison, but Ferdy rescues her and shoots it point-blank, damaging its laser just before he falls unconscious. Despite an injured leg, Allison escapes into Ellis Paint Company and sets up a trap by mixing paint and chemicals. Allison then lures Protector 1 inside, where it gets stuck, unable to get traction on the spilled paint and thinners. Allison then tosses a flare into the store, igniting the chemicals and finally destroying Protector 1. As daylight appears, Allison leaves the store and Ferdy awakens. The two remain the only survivors.

In a post-credits scene, a fourth, unknown Protector says its catchphrase "Have a nice day" one last time.

Allison ultimately destroys the last killer robot and survives until dawn, the sole survivor of the massacre.

The ending cements the film's blend of horror and dark comedy, as Allison's resourcefulness and tenacity allow her to outwit the relentless machines. The sunrise offers a tongue-in-cheek sense of relief, highlighting both the absurdity and the thrills of surviving a night in a mall gone mad.