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...
| Directing | Pascal Thomas | Director |
| Writing | Clémence de Biéville | Adaptation |
| Writing | Pascal Thomas | Adaptation |
| Writing | Nathalie Lafaurie | Dialogue |
| Writing | Clémence de Biéville | Dialogue |
| Writing | Clémence de Biéville | Scenario Writer |
| Writing | Nathalie Lafaurie | Adaptation |
| Writing | Pascal Thomas | Dialogue |
| Writing | Nathalie Lafaurie | Scenario Writer |
| Writing | Pascal Thomas | Scenario Writer |
| Writing | Agatha Christie | Story |
