A parade of various animals leads piano-playing Krazy and his likewise opponent, a Lion, to a large, crowded arena where they square off in the boxing ring to play a musical duel. The Lion has an upright piano, and plays a bit though a fly keeps bothering him. Krazy has a grand piano, and plays a little too, but soon it's between rounds, and all four competitors (the pianos are living creatures also) are exhausted. Then the pianos go at it alone in a punch out, Krazy and the victorious Grand start a spirited playing of "St. Louis Blues", and the Lion and Upright join in as well. All take a bow at the end.