Michel Thierry is asked by the Second Bureau to go to Provence to help two colleagues, Leroy and Orcado, who are monitoring a gang of arms dealers. As soon as he arrives, Orcado is shot and leaves him an incomprehensible message in which three words are written: Sarah, Métis, Yerco...
| Actor | Role |
|---|---|
 Frank VillardCapitaine Thierry | Capitaine Thierry |
 Barbara LaageMariana | Mariana |
 Olivier MathotLieutenant Leroy | Lieutenant Leroy |
| GGérard BuhrYerco | Yerco |
 Fernand FabreSkyriadès | Skyriadès |
 Albert DinanGeorio (as Dinan) | Georio (as Dinan) |
| HHenri San JuanNot listed | Not listed |
 Maurice ChevitNot listed | Not listed |
| AAlfred GoulinNot listed | Not listed |
 Jean DegraveNot listed | Not listed |
 Pierre MiratNot listed | Not listed |
| HHenri RiouNot listed | Not listed |
 Georges MontantNot listed | Not listed |
| RRobert CharletNot listed | Not listed |
| JJacques BézardNot listed | Not listed |