The adventures of the famous Joseph Rouletabille, an adventurous young journalist, gone to solve a murder in the south of France. He puts an end to the conflict between two rival bands for the possession of a revolutionary metal, belenium.
| Actor | Role |
|---|---|
 Jean PiatJoseph Rouletabille | Joseph Rouletabille |
| SSuzanne DehellyFlorine | Florine |
 Marie DéaWanda | Wanda |
 Jérôme GoulvenÉric | Éric |
 Lucas GridouxProfessor Sadjeck | Professor Sadjeck |
 Claire GuibertNot listed | Not listed |
 Léo LaparaAmbassador | Ambassador |
| YYette LucasNot listed | Not listed |
| AAriane MuratorNot listed | Not listed |
 Monique MélinandLisette | Lisette |
 Claude NicotFifrelin | Fifrelin |
 Véra NormanNot listed | Not listed |
 Roger VincentDoctor | Doctor |
 Michel VitoldArnauld | Arnauld |