Biologist Alex Brisco develops a new method to communicate with chimpanzees. Instead of using machines, she teaches the chimps simple sign language. Her research is overlooked by ignorant colleagues, but one man, Mark, a cellist, helps Alex with her research.
| Actor | Role |
|---|---|
 Karen AllenAlex Bristow | Alex Bristow |
 Armand AssanteMark Mathias | Mark Mathias |
 Josh MostelMel Gorsky | Mel Gorsky |
 Holly HunterCoral Grable | Coral Grable |
 Richard LibertiniDoctor Parrish | Doctor Parrish |
 Joyce BrothersHerself | Herself |
 Alice DrummondSite Committee | Site Committee |
 Nan MartinMrs. Norton | Mrs. Norton |
 Alexa KeninNot listed | Not listed |
| JJon MatthewsTyler Forbes | Tyler Forbes |
| CCrystal BudaCleo Grable | Cleo Grable |
 Ivan BonarDr. Ridley | Dr. Ridley |
| VVivian WarfieldBlaze de Teo | Blaze de Teo |
 Janni BrennMrs. Parrish | Mrs. Parrish |
| SSteven Kent FosterNerd | Nerd |
| CCynthia VanceCo-Ed | Co-Ed |
| Joyce BrothersVisiting Psychologist | Visiting Psychologist |
| AAl JonesSite Committee | Site Committee |
| PPeter ProuseSite Committee | Site Committee |
| Alexa KeninSheila Sandusky | Sheila Sandusky |
| DDan J.P. CierniaStudent (uncredited) | Student (uncredited) |