On its way back to Earth, the space shuttle Nautilus passes through a cloud of alien spores causing its sole occupant, astronaut Steve Thomas to transform into a blood-thirsty monster. The shuttle crashes into a swampy region of central Florida, creating a situation which threatens contagion and/or death to all who encounter the shuttle or its mutated pilot.

One Halloween night, a little girl visiting the Burber family's "House of Horrors" attraction is brutally hacked to pieces by their young son, Eddie. Having fled the scene, Eddie is taken away by his mother to live in solitude at a remote cabin. Twenty years later, Tophill State College's Sigma Phi fraternity are desperately trying to raise some cash, so they decide to throw a raucous fundraiser party for their peers. In the midst of the festivities, a mysterious figure arrives at the door, offering them the key to the old abandoned Burber house and suggesting that they turn it into a haunted house. Seizing the opportunity, the youngsters quickly set about transforming the property into an elaborate — and potentially lucrative — Halloween attraction. Little do they realize that Eddie Burber has returned home and intends to have some All Hallow's Eve fun of his own — setting up his own "Kill Room," where the line between fantasy and reality quickly becomes blurred...