Three identical music boxes manufactured by an inmate at Dartmoor Prison are sold to three random collectors at an auction house in London. A female antagonist (Patricia Morison) and her accomplices attempt to recover the music boxes using all means possible, even murder.

Watson’s old schoolmate, Julian “Stinky” Emery, purchases one of the boxes. After an evening of entertaining Sherlock Holmes and Dr. Watson, Emery is murdered and robbed of the recently purchased music box. Holmes and Watson investigate and begin to realize that the music boxes contain more than just a swaggering Australian folk tune.