Raffles is an English gentleman with a secret life—he is the notorious jewel thief known as "The Amateur Cracksman." While sailing from India to England accompanied by his friend, Bunny Manners, it is rumored that the infamous cracksman is aboard ship. Raffles warns a lady passenger to keep an eye on her necklace, which is stolen soon afterward. Although a search reveals no evidence, the necklace is returned upon reaching London.