A series of knife murders have an odd feature about them; the victims find that their luggage has been packed for them just before their deaths. Scotland Yard investigates, and discover that the murders are linked to an addictive drug called Mescadrine.

Carlo del Ponte, a pop star celebrated in the U.S., travels to his hometown of Santa Clara, Italy, to take some time off. Not only does Carlo find himself caught up in an armed robbery there, but his pretty cousin Antonella is missing her father and believes he has fallen victim to the old family feud between the del Pontes and the Tartinis. Now Carlo is supposed to help resolve the matter as peacefully as possible.

The enterprising Anton Klapproth runs a flying duck farm in the Eifel, but now he finally wants to experience a real adventure in the big city of Cologne. A visit to a sanatorium for the mentally ill seems particularly sensational to him, as there is certainly a lot going on there with the "Jecken" and would provide plenty of story material for his regulars' table. In return for a loan, Anton's nephew allows his uncle to stay at the Pension Schöller. However, the guests there are by no means mentally ill, just rather eccentric. However, the unsuspecting Anton has a great time, thinking he is in a psychiatric institution.

Heinz Erhardt wanders through the Black Forest as a photographer for a magazine. On the train he meets a young girl who from now on does not leave his side.