What\'s our idea of a bad joke? Spending $3.8 million on a vintage 1937 Mercedes-Benz, shipping it half way around the world, and then having it seized by foreign police comes pretty close.In any event, Dutch car collector Frans van Haren certainly wasn\'t laughing when his ultra-rare 1937 Mercedes 500 K Roadster, bought at an RM Auctions event last year for $3.767 million, was seized by German police while it was on display at the Techno Classica car show in Essen, Germany.Jalopnik explains that the car was seized following a claim made to the police by a custodian acting on behalf of the family of German industrialist Hans Friedrich Prym, the car\'s first owner.Prym\'s heirs believe the rare 500 K - only 392 were made, just 29 of which were bodied as roadsters - was stolen, and not sold to an American soldier in 1945 as is believed.With the car returning to the country where the alleged crime took place, this is the first time police have been able to seize the car and resolve the longstanding issue over the car\'s provenance.