Doctor Gachet's Portrait

A painting entitled "Portrait of Dr. Gachet" has been stolen one night from a museum. News reports immediately spread, and our heroes set off in pursuit of any clues that might lead them to the thief. After traveling through several countries following their trail, they discover that the theft is the work of a smuggling ring, led by Minister Goring, whose loot includes a vast quantity of paintings stolen from private collectors, with the intention of transporting and hiding them beyond their borders.