Matthias Duval is in love, but he can't choose between the two twin sisters Betty and Liz Kerner. To pick up the two sisters, he invents his own twin brother and will play both characters.
| Actor | Role |
|---|---|
 Pierre RichardMatthias Duval / Mathieu Duval | Matthias Duval / Mathieu Duval |
 Camilla MoreElisabeth 'Betty' Kerner | Elisabeth 'Betty' Kerner |
 Carey MoreElizabeth 'Liz' Kerner | Elizabeth 'Liz' Kerner |
 Jean-Pierre KalfonErnest Volpinex | Ernest Volpinex |
 Andréa FerréolEvie | Evie |
 Jacques FrantzRalph | Ralph |
 Jean-Pierre CastaldiCharlie | Charlie |
 Paul Le Personle clochard jazz | le clochard jazz |
 Jean-Claude Bouillaudl’inspecteur | l’inspecteur |
 Henri Labussièrele maire | le maire |
 Françoise DornerNot listed | Not listed |
| IIsabelle StrawaNot listed | Not listed |
| PPaul ClaudonNot listed | Not listed |
 Gérald CalderonNot listed | Not listed |
| AAlain HuylebroeckNot listed | Not listed |
| GGladys BerryNot listed | Not listed |
| SSean O'NealNot listed | Not listed |
| AAjzyk SpigelmanNot listed | Not listed |
| Andréa FerréolNot listed | Not listed |
 Yves Robertl’homme dans l'ascenseur | l’homme dans l'ascenseur |