Plot
On a restricted side of a Utah mountain, Dr. April Sommers is working to create a new breed of spider with several other scientists. Chad, a new teen arrival to the ski resort side of the mountain, challenges ski resort worker and retired Olympic skier Dan "Dash" Dashiell to a race. During the contest, Dash turns away from a large rocky slope rather than risk a leg injury like the one that ruined his career, and meets Dr. Sommers as he makes it to the bottom. Frank Stone takes the teens inside his resort. Dr. Sommers returns to the lab, where she finds everyone dead, except for one survivor cocooned in a spider web. Before the survivor dies, he warns Dr. Sommers about the spiders escaping. The last spider remaining at the lab, a mutated black widow, attacks Dr. Sommers and forces her into a locked office. She sounds an alarm, alerting Professor Marks and Army Captain Baker, who are elsewhere on the mountain.
Back at the lodge, Dash meets up with Ranger Rick,who asks for assistance finding two missing hunters. They find the hunters' truck, and a mutilated elk Dash assumes to have been killed by a bear. Dash and Rick locate one of the hunter's bodies, and encounter the other cocooned in a large spider web. As Dash and Rick turn to run, Rick is snagged by a web and killed by a spider. Dash makes it back to the hunters' truck and hot-wires it to get away.
Back at the lab, Professor Marks, Captain Baker, and a squad of soldiers enter the compound. The spider attacks and kills one of the soldiers. Dr. Sommers steals records of the experiment and realizes Professor Marks deliberately accelerated the spiders' growth, which makes them larger, faster, and stronger. However, it also causes them great hunger and prevents the cold from killing them. Sommers had been desperate to obtain sufficient amounts of spider webbing for new armor ideas.
Dr. Sommers meets up with Frank and Johnny at the lodge, which has been invaded by the spiders. Frank and Dr. Sommers watch the spiders kill several guests, including the teens' ski coach. Later, Frank sees the teens hiding in a shed and leads them to a bus. Chad gets the keys and drives off, but when a black widow crawls onto the windshield, Chad crashes the bus into a snow bank. Dash returns to the hotel and helps secure it. When he and Dr. Sommers search the basement, a spider gets in and almost attacks them, but they stun it with a fire extinguisher and lock it in the basement. Back in the lobby, a spider crawls in through the chimney and kills two guests before Dash impales it with the antlers of a mounted deer head.
Meanwhile, on the crashed bus, Frank checks the area and makes sure the kids are okay. However, one of them is unconscious and injured. The group thinks of a way to exit the bus as the black widow tries to get inside. Eventually, Frank traps the spider and the kids escape. Frank is nearly killed, but is rescued thanks to the timely arrival of Captain Baker and his squad. Back at the lodge, Dash devises a plan with Captain Baker to trap the spiders. Dash takes his skis and leads the spiders to a snowboard half-pipe, which Baker and his men are blocking off. Johnny heads toward an avalanche cannon and waits for Dash's signal. At the half-pipe, the spiders are captured and Dash signals Johnny, who blows the spiders up. Professor Marks, who had been opposed to killing the spiders, charges at Dash and tries to kill him. Marks falls down the side of the half-pipe towards the last spider, which kills him as Baker shoots the beast.
A government agent arrives with a group of soldiers that begin destroying all traces of the spiders. The agent demands that the survivors keep quiet about recent events and says that the "official" explanation for what happened will be that there was a spill of hallucinogenic chemicals.
