The Disobedient Mouse (1938)

Baby-Face Mouse, disobeying his mother, goes into the territory of Rat Enemy No.1. The gangster is working on turning the young mouse into a member of his gang, but Baby-Face gets so tough he knocks out Rat Enemy No. 1 and turns him over to the police and gets a reward. Back home though, he gets spanked for crossing the railroad tracks into bad territory.