After a black hole strikes, it opens up another dimension in a rural Wisconsin town, and soon there is an invasion of gigantic arachnids who crave human flesh. NASA scientists Dr. Vance (Steve Brodie) and Dr. Jenny Langer (Barbara Hale) try their best to save humanity as a romance blooms between them. Meanwhile, local Dan Kester (Robert Easton) squabbles with his wife, Ev (Leslie Parrish), and has a dalliance with local bartender Helga (Christiane Schmidtmer).