The jet-setting crimebusters head for Germany, where Jennifer is due to donate bone marrow to a leukaemia patient. But when the surgeon's fiancee is kidnapped, she agrees to pose as the missing woman in a bid to uncover her captors. Feature-length spin-off of the detective series, starring Robert Wagner and Stefanie Powers.

On a mission of mercy, Jennifer Hart is in Germany to donate bone marrow to Maximilian, a young leukemia patient. Following the operation, she plans to spend a romantic anniversary in Munich with her husband Jonathan. The bone marrow clinic's director, Peter Donner, is surprised by Jennifer's uncanny resemblance to his French fiancée, Simone Grohe. When she goes missing, Jennifer steps in to play the role of Simone to save Peter the embarrassment of an explanation to his cousin and benefactor Karl von Ostenberg at the lavish engagement party. But, of course, it is Karl who kidnapped Simone - in order to control the fate of Peter's inheritance - and now Jennifer is in as much danger as Simone! Once again the Harts tackle danger and mystery with their usual devil-may-care charm and romance