Robert Douglas

A kingdom's ascending heir, marked for assassination, switches identities with a lookalike, who takes his place at the coronation. When the real king is kidnapped, his followers try to find him, while the stand-in falls in love with the king's intended bride, the beautiful Princess Flavia.

Roger Quain, escorting two zoo-bound black panthers on the train from Milan to Paris, is unaware that a Western agent, Catherine Ullven, has hidden a microfilm in the collar of one of the animals. But when the train is derailed in the Swiss Alps and the panthers escape, she is forced to involve him in her mission, which now ...