James Ryder was an attendant at the Hotel Cosmopolitan in London. He stole the Blue Carbuncle, a precious jewel, room of its owner, the Countess of Morcar, with the help of her maid Catherine Cusack. The pair tried to frame John Horner for the theft, but Sherlock Holmes discovered the truth. However, because Holmes judged Ryder was unlikely to become a career criminal, and because it was Christmas, Holmes let Ryder go free. Afterwards, Ryder fled to continental Europe.