April and Mark are in Venice to capture Horsch, a top-ranking crook. April manages to grab him and the three set off for the Yugoslavian border. When border guards board the train on which they are passengers, Horsch escapes. April gives chase, following him to a villa where she is captured and drugged. Meantime, Mark is trying to trace April and they eventually uncover a plot to loot the Vatican.
Elenco: Leo G. Carroll , Noel Harrison , Stefanie Powers .