A variety of suspicious characters try to get their hands on a priceless diamond necklace aboard the Orient Express.
An insurance company hurt by a string of jewel thefts decides to smoke out the international community of thieves by putting the priceless Karenina diamond necklace up for auction. There are many interested parties, but jewel dealer Pierre Londais ultimately wins the bidding. Among the suspicious characters interested in the diamonds are a young woman named Odette Mauclair, a wealthy American named Colonel Jackson, and the mysterious Baron Von Kampf. There are robbery attempts at Londais's Paris hotel and later aboard the train to Istanbul. When the diamonds go missing, everyone aboard the train is a suspect.—Jimmy L.
Ricardo Cortez plays a jewel dealer who hopes to provoke, and catch, an international jewel thief, so he transports the famous Karenina diamonds from Paris across Europe to Istanbul on the Orient Express, along with a trainload of suspicious characters.
