Inspector Dupin finds himself entangled in several mysteries at once: the discovery of a corpse on a remote Atlantic island, the mystery surrounding a Celtic musical instrument, and the search for the true cause of a tragedy.
| Actor | Role |
|---|---|
 Pasquale AleardiGeorges Dupin | Georges Dupin |
 Jan Georg SchütteKadeg | Kadeg |
 Gisa FlakeLeonie Nevou | Leonie Nevou |
 Franziska WulfNolwenn | Nolwenn |
 Hildegard SchmahlSybil | Sybil |
 Sithembile MenckRomy Saux | Romy Saux |
 Luise AschenbrennerRayanne Ker / Simone Dulac | Rayanne Ker / Simone Dulac |
 Amal KellerCéleste Bourvil | Céleste Bourvil |
 Franziska von HarsdorfEnora Gaec | Enora Gaec |
| LLaurenz LerchRoderic | Roderic |
| MMatthieu SvetchineMathis | Mathis |
 Josefine KellerBrigitte | Brigitte |
 Paul AhrensEric | Eric |