The player controls Harley, a man in a green suit who has shrunk himself to size of a bar of soap. The player's mission is to gather parts of Harley's (presumably) now-destroyed shrinking machine to return him to normal size. As the player advances through levels, they pick items such as tacks, rubberbands and marbles. The many locations the player adventures through is Harley's lab where the initial incident occurs, Harley's Kitchen, Harley's toy room, where the player pilots a toy tank by himself, Harley's Bathroom, and other stages.