Betty Boop is busy in the kitchen showing off her usual attributes, along with her cake-baking skills which she displayed more than once, and answers the doorbell to find Irving the Imbecile Idiot on her doorstep. After enduring several practical jokes at the hands of Irving, Betty hotfoots it upstairs to the room of Professor Grampy, who appears, we hope, to be a paying boarder, to enlist his aid in dealing with Irving. Grampy, per usual, puts on his thinking cap with the built-in light-bulb that lights up when Grampy gets an idea about how to handle a situation. His ideas always involve a Rube-Goldberg machine-device of some kind, and he uses them against Irving. But the last joke is still on Betty and Grampy.