A sailor in a pub returns to his table and finds a chicken claw tied with a black ribbon hanging over it. He angrily accuses a barmaid of putting it there, but she denies it. Just after the sailor leaves the pub, he is stabbed to death. Inspector Lestrade consults Sherlock Holmes about the case, and when he tells Holmes that this is the second recent murder that has involved a chicken claw tied with a black ribbon, Holmes explains that this is used as a death threat in certain parts of Trinidad. Soon afterward, when a doctor receives the same objects, he consults with Holmes, Lestrade, and Dr. Watson.—Snow Leopard (IMDb)