A man has been killed on the Dover/Boulogne car ferry. What is the connection between him and the attempts being made to kill Jane Kerrell (Eve Renzi), a young girl in her early twenties? As she speeds through the French countryside to the South of France, several attempts are made on her life as she is deliberately forced off the road by another car. But when she reports these attempts, the local Cap Ferrat Police Inspector and the sinister psychiatrist, Dr. Forla (George Pravda) believe these attempts are in her imagination and Dr Forla, concludes that Jane is mentally disturbed. At her wits end Jane finds an ally in the young English painter, Paul Hedley (David Buck) who finally believes her life is in danger following an attempt to murder him. When Inspector Malling of Scotland Yard (Peter Vaughan) and Mr. Breese (Francis Matthews) arrive in Cap Ferrat trying to uncover the connection between Jane and the murdered man on the ferry, this thrilling puzzle of international intrigue begins to unravel against the backdrop of the French Riviera.