Prudence and Bélisaire Beresford have decided to take things easy. But when a rich Russian heiress disappears, Prudence can't resist and Bélisaire is forced onto the adventure. Their investigation will put them on the trail of a mysterious scientist who holds the secret to eternal youth...
Prudence Beresford
Catherine Frot
Bélisaire Beresford
André Dussollier
Doctor Nicolas Roscoff
Nicolas Marié
Doctor Matarazzi
Agathe de La Boulaye
Marie Van Dinh
Linh-Dan Pham
Doctor Jünger
Éric Naggar
The General
Bernard Verley
The family doctor
Hervé Pierre
Marie-Christine
Sarah Biasini
Rudi
François Bettens
Prudence's father
Julos Beaucarne
Hector
Alexandre Lafaurie
Miss Sakhaline
Katia Tchenko
The Countess
Marie-Christine Demarest
Gisèle
Ophélia Kolb
The receptionist
Léa Wiazemsky
A policeman
Luc Palun
The nude model
Isabelle Migotto