A messenger delivers an invitation to Betty Boop to come over to Grampy's house for a party and bring the gang. The delighted Betty goes down the street singing "I'm on My Way to Grampy's" and is joined by a fireman who is rescuing a damsel-in-distress but tosses her back in the burning building in favor of following Betty...anywhere; a policeman who deserts his traffic-directing at a busy intersection; and two moving men. Betty and her gang arrive at Grampy's, and Grampy shows off a few of his Rube-Goldberg inventions while serving punch-and-cake. Betty thinks the party needs a little music, so Grampy employs several of his contraptions and devices, and all hands are soon dancing to the Hoosier Hotshots' version of "Tiger Rag."