TV model Maddie Hayes, after being swindled by crooked managers, is forced to join forces with street-smart David Addison to run her unprofitable detective agency. David and Maddie get more and more involved with the murder mystery and the new-found watch. It isn't long before the watch attracts a lot of unwanted people, among them the mob and Heinz, a wicked old man. The duo know the watch somehow holds the key to the location of the diamonds, but what they don't know is how Intricate the operation will be to find out.They become involved in the murder mystery involving a seemingly worthless old watch. Maddie and David take the wristwatch to a pawnbroker to assess it and he finds numbers etched on the inside plate. Later they question Susan, Kaplan's widow, and she tells the wristwatch was a memento from his father, a German pilot.