The residents of a suburban high-rise apartment building are infected by parasites that turn them into mindless nymphomaniac fiends.
| Roger St. Luc | Paul Hampton |
| Rollo Linsky | Joe Silver |
| Nurse Forsythe | Lynn Lowry |
| Nicholas Tudor | Allan Kolman |
| Janine Tudor | Susan Petrie |
| Betts | Barbara Steele |
| Merrick | Ronald Mlodzik |
| Detective Heller | Barry Baldaro |
| Mr. Guilbault | Camil Ducharme |
| Mrs. Guilbault | Hanna Poznanska |
| Doorman | Wally Martin |
| Kresimer Sviben | Vlasta Vrana |
| Benda Sviben | Silvie Debois |
| Delivery Boy | Charles Perley |
| Parkins | Al Rochman |
| Miss Lewis | Julie Wildman |
| Mr. Wolfe | Arthur Grosser |
| Olive | Edith Johnson |
| Vi | Dorothy Davis |
| Mona Wheatley | Joy Coghill |
| Elevator Mother | Joan Blackman |
| Elevator Daughter | Kirsten Bishop |
| Emil Hobbes | Fred Döderlein |
| Garbage Room Man | Sonny Forbes |
| Laundry Woman | Nora Johnson |
| Annabelle | Cathy Graham |
| Boy | Robert Brennen |
| Girl | Felicia Shulman |
| Bearded Man | Roy Wittan |
| First Elevator Man | Denis Payne |
| Second Elevator Man | Kevin Fenlow |
| Infected Crowd Member (uncredited) | David Cronenberg |
