Karen Allen
(Alex Bristow)
Armand Assante
(Mark Mathias)
Josh Mostel
(Mel Gorsky)
Holly Hunter
(Coral Grable)
Richard Libertini
(Doctor Parrish)
Jon Shear
(Tyler Forbes (as Jon Matthews))
Nan Martin
(Mrs. Norton)
Crystal Buda
(Cleo Grable)
Ivan Bonar
(Dr. Ridley)
Vivian Warfield
(Blaze De Teo)
Janni Brenn
(Mrs. Parrish)
Steven Kent Foster
(Nerd)
Cynthia Vance
(Co-Ed)
Joyce Brothers
(Visiting Psychologist (as Dr. Joyce Brothers))
Alice Drummond
(Site Committee)
Al Jones
(Site Committee)
Peter Prouse
(Site Committee)
Alexa Kenin
(Sheila Sandusky)
Dan J.P. Ciernia
(Student (uncredited))
Mike the Chimpanzee
(Himself)