 Lupin meets Fujiko who is seeking The Star of Killamanjaro diamond from a mob boss. But the Mob Boss wiped out his memory which made him forget what happened 6 months ago. And died shortly from heart failure. The diamond is in fact implanted in his chest. And will require surgery to recover it. Lupin and his gang must go after the ambulance that s departing the corpse of the Mob Boss and retrieve the diamond. But it won t be easy with Inspector Zenigata and the police escorting the ambulance on the way to the morgue.