when yates arrives, he prepares to arrest deets upon finding many severed hands pinned to a wall in deets' home, but stands down upon realizing that the hands on the wall appear to be right hands, not left hands, because the thumb on yates' own left hand points to the left, cluelessly failing to realize that he is looking at his hand with its palm facing up, in the opposite orientation of those on the wall. yates, leaves, not knowing that cartman is bound and gagged in deets' basement, but he questions his own observation about the hands. he goes back to the station, and after a montage depicting running elaborate criminology tests, exercising, and even losing track of what he was doing, he figures out his mistake, and returns to deets' house, where he shoots deets just before deets kills cartman.