The Jewish antiques dealer Siegfried Rabinovicz is on his way from New York to Hamburg where he is about to testify as the principal witness in a murder case. During a stop-over, an airport hostess talks him into giving up his seat on the connecting flight to another passenger. While Rabinovicz is waiting in the VIP lounge, he gets into a conversation with a stranger who is remarkably well informed about the murder Rabinovicz is going to testify about.