Strange Affair (1944)

Dr. Brenner is organizing a banquet for war refugees, when he receives a phone call from his friend Baumler, who fears someone is trying to kill him. Preoccupied with work, Dr. Brenner passes on the responsibility of meeting Baumler to his friends: Bill, the creator of a comic strip sleuth, and his wife, Jacqueline "Jack" Harrison. At the banquet that night, Baumler seemingly dies of a sudden heart-attack. Bill suspects he has been poisoned. However, Jack suspects her husband is more interested in a woman involved in the case. So while Bill follows clues, Jack follows Bill.