Stanislas Oscar Seminario, aka SOS, is a young explorer, just back from Africa, visiting old friends: the Pescara's. But the father keeps receiving anonymous letters. And soon a mysterious murder is committed. SOS begins to investigate...
Cast: Paul Meurisse, Micheline Francey, Gilbert Gil, Pierre Renoir, Jean Tissier, Pierre-Louis, Junie Astor, Jean Debucourt, Jean Brochard, Mady Berry
