Newlyweds Peter (David Manners) and Joan Alison (Julie Bishop (actress)), on their honeymoon in Hungary, learn that due to a mixup, they must share a train compartment with Dr. Vitus Werdegast (Béla Lugosi), a Hungarian psychiatry. Eighteen years before, Werdegast went to World War I, never seeing his wife again. He has spent the last 15 years in an infamous internment in Siberia. On the train, the doctor explains that he is traveling to see an old friend, Hjalmar Poelzig (Boris Karloff), an Austrian architect.