Young - beautiful - married, fulfilled, Martha is bored. Passive in an active society, she took a first step by serving as a "guinea pig" to her brother researcher who undertook a comparative study on animal behavior and human behavior.
| Actor | Role |
|---|---|
 Dominique LaffinMarthe | Marthe |
 Jean-Luc BideauDoctor Vernier | Doctor Vernier |
 Christine MurilloLouise | Louise |
 Marcel MaréchalPierre, Marthe's husband | Pierre, Marthe's husband |
 Jean-Pierre SentierMan from the dump | Man from the dump |
 Jacques DenisTao, Marthe's brother | Tao, Marthe's brother |
 Monique ChaumetteMarthe's mother | Marthe's mother |
 Victor GarrivierProfessor Bronstein | Professor Bronstein |
 Charlotte Maury-SentierConcierge | Concierge |
| FFrançois CalvezChristian | Christian |
 Amandine RajauIsabelle | Isabelle |
 Jean AmosDelivery man | Delivery man |
| JJean de ConinckWomanizer on the bridge | Womanizer on the bridge |
| GGuy DhersAgent of rat extermination | Agent of rat extermination |
 Alain FrérotRat man | Rat man |
 Maurice BénichouRat speaker | Rat speaker |
 Daniel LalouxSpeaker's assistant | Speaker's assistant |
 René MorardGuardian | Guardian |
 Jean-Roger MiloStudent | Student |
 Daniel RussoNurse | Nurse |
| GGérard Sargue2nd nurse | 2nd nurse |
 Patrick BraoudéStudent (uncredited) | Student (uncredited) |