While boys play baseball in the street, Poggle tries to collect rent from a tenant in Mr. Harmon’s tenement. She refuses, and the boys chase him off. Bedraggled, Poggle goes to Homer Van Dine Harmon’s grand apartment and Homer offers to show him how to handle hoodlums. They’re driven to the tenement and emerge in the middle of a huge street fight. Margie, a resident, thinks that Homer has hit her brother Clipper, so she slugs him. He’s entranced by her. The cops come in and break up the fight.
In a pool hall, Clipper delivers a wallet he’s stolen to Butch, a local tough.
The next day, in Children’s Court, Clipper testifies about how the fight started. After another fight almost erupts, Homer takes the stand. The sight of Margie inspires him to take the blame for the fight. He pays a $100 fine. Outside, Margie blames Butch for all of Clipper’s troubles, and Clipper slaps her. Homer intervenes, and offers to build a place for the kids to play. She softens towards him, and he buys her a potted plant, which promptly breaks.
Homer gives a dedication speech at the gym he’s built, Harmony Hall. Only one small boy and his dog listen. The boys play baseball in the street, where Clipper discourages them from visiting the Hall. Margie visits Homer at the gym, and tells him not to give up so easily. He goes to the ball game and catches a fly ball in his top hat. The boys chase him into the gym. They stay to try out the equipment, but they don’t know how to use it so they quickly get bored and decide to leave. Margie offers them a wrestling match, so they stay. Homer and Poggle wrestle badly, and Homer wins. One kid asks for lessons from Homer, but he’s a ringer. He throws Homer around the gym several times. Then Poggle decides to hire One-Round Mulvany; for $50, he’ll let Homer knock him out. They box. Between rounds, Butch offers him another $50 to knock out Homer. He takes it, but eventually, after a beating, Homer knocks out Mulvany.
At the pool hall, Butch presents his new plan to Clipper: dressed as a blond woman, Clipper will help him with robberies.
At Margie’s apartment, she and Homer prepare a birthday celebration for Clipper. He’s underwhelmed. He steals Homer’s watch and climbs out the window. Margie cries and Homer tries to make her feel better by serving her some duck. However, he does a terrible job at carving. A cop brings Clipper in, but Homer tells him that the watch was a birthday present. Margie kisses him.
In a record store, Homer tells Poggle that he doesn’t know how to propose to Margie. Poggle suggests making a recording, so he does, reading a series of sentimental song titles until he gets to “Yes, We Have No Bananas.” At that point, he offers to kick Poggle in the pants.
At Homer’s place, he plays the record for Margie. He scrambles to take it off when the kick in the pants remark plays.
Butch and Clipper (who’s in drag) drive away from their crime scene. Meanwhile, Marie and Homer arrive at the gym for the big musical tragedy show. He tells Poggle that Marie will marry him if he’ll do something for Clipper. Homer looks down at a car parked below and sees a man undressing a blonde woman. Then he sees Clipper, and assumes that he was the masher. He lectures him in the locker room. Clipper thinks that Homer is talking about the stick-up racket. He tells Butch, and Butch tells him to use real bullets when he shoots Homer in the show. Clipper refuses, but Butch insists.
The show begins. Poggle plays the Duke, and Homer is Sonia, his commoner passion flower. Clipper comes in to rid the country of the woman who would plunge their country into darkness, but he can’t bring himself to pull the trigger. Poggle wrestles with him for the gun, it goes off towards a corner, and Sonia dies melodramatically.
In the locker room, Homer looks for his costume for the next act. He can’t find the right one, so he uses Clipper’s female disguise. Butch confronts Clipper, tells him to be outside in five minutes, and then leaves. Margie comforts Clipper and refuses to believe that he’s the blonde bandit. He runs out. Homer, in drag, comes in and runs after him. Lefty pushes Homer into Butch’s car and they speed off.
In the car, Butch explains that Clipper/Homer must plug Homer at his apartment. Meanwhile, the real Clipper goes to the pool hall, and Lefty realizes that the wrong person went with Butch. His gang rushes to Homer’s, leaving one member to guard Clipper. At Homer’s place, Butch realizes that the blonde woman isn’t Clipper. His gang arrives and chases Homer to the bedroom. Clipper hits the guard and convinces the boys to follow him to Homer’s, where they beat up the gangsters. Homer throws Butch around the room several times while Margie watches. When she hugs Homer, he throws her too — but she responds to his “Oh Margie!” with a much sweeter “Oh Homer!” — Lisle Foote