You Don’t Know What You’re Doin’!
The story involves the character Piggy, who picks up his girlfriend Fluffy and takes her to a theater where a hot jazz orchestra is playing. Piggy mocks the trumpet soloist, and plays a corny chorus of the 1873 hit “Silver Threads Among the Gold” on the saxophone. The audience, led by three drunk dogs in the balcony, then mock Piggy with the title song “You Don’t Know What You’re Doin'”. Piggy is then joined onstage by one of the drunk dogs (a black dog, perhaps a prototype of Goopy Geer). The dog starts to drink a bottle of bootleg hootch that he has (the film was made during alcohol Prohibition in the USA), and belches in Piggy’s face, causing him to get drunk. Piggy snatches the booze and runs out of the theatre with the dog chasing him. He pours some of it into the radiator of an automobile, which arches its back like a frightened cat and takes Piggy for a wild ride through the city. The dog continues to chase after Piggy, but both of them eventually end up in the back of a truck which dumps them into a trash can. Both of them shout out “Whoopee!” as the cartoon comes to an end.
Plot summary: Wikipedia