Sherlock Holmes runs into competition from an American private eye, Shadwell Rafferty on a visit to 1896 Minnesota. Both men are trying to solve a murder during the winter carnival in St. Paul, its victim a wealthy man whose head was found in a block of ice.
Learning that a presumed-dead killer is alive and keeping a hostage, Sherlock Holmes sets out across multiple continents accompanied by Irish saloon keeper Shadwell Rafferty, but finds the case complicated by someone who is impersonating him.