A trip to Africa turns into an unusual kind of safari for our reporter friends. Spirou and Fantasio, during a daring night investigation, encounter a wounded man who is running from mysterious men. He claims they bombed an automobile factory to steal the plans of a highly advanced prototype, and that he took half of the plans and ran. Having sworn to take the documents back to their owner--who has the other half--the two adventurers are soon on their way to Africa. But of course, the bandits are in hot pursuit...