A club of seven wealthy men ("The Good Comrades") lives together in a Scottish castle (how chummy!). But that's not all. Each member has taken out a large insurance policy with the beneficiary to be the last surviving member of the club. After two clubmates mysteriously die, Sherlock Holmes (Basil Rathbone) and his assistant, Dr. Watson (Nigel Bruce), are called in to investigate. The only clue? A letter containing -- strangely -- orange seeds.