Sergeant Preston had been summoned to the office of Inspector Maynard at Mounted Headquarters in Dawson City. The great dog King rested at his master's feet as they listened to the Inspector saying "Sergeant, have you ever heard of a crook called The Sparrow?" It's been said that he's just about the slickest crook in the States, although that might be narrowed down now, as he is reputed to be on his way to the Yukon...