A not yet one-year-old boy, abandoned on a landing in a tenement house in New York's "Hell's Kitchen," is adopted by three men who live on that floor: German delicatessen owner Herman Schultz; Jewish tailor Abie Katz; and Irish street cleaner Patrick O'Malley. The men, although ignorant in the ways of infants, rear the child, whom they call "Mike." After the boy finishes high school, they plan to send him to college, but Mike wants to work rather than be a burden to them any longer. However, when Mary, their Italian-American neighbor who works as Herman's cashier, joins the men in trying to convince Mike otherwise, he agrees to go to Yale. On his twenty-first birthday, the three "fathers" have prepared a lavish banquet for Mike, now captain of the varsity crew and very popular, so that he could meet leading politicians, bankers and businessmen who might offer him a good job. Before going to the banquet, Mike gets drunk at a cocktail party to which he is lured by Evelyn Joyce, who is attracted to him. When he finally arrives at the banquet, the prominent people leave, insulted by his drunken behavior. When Mike later angrily turns against his three fathers, Patrick knocks him out. Back at college, Mike begins to gamble and gets in debt to Henry Sharp, a crooked gambler. Sharp threatens to have Mike arrested for writing a bad check unless he throws the upcoming Yale-Harvard crew race, but when Mike sees that his three fathers and Mary have come and are betting on him, he rows the team to victory. When Sharp threatens the fathers with sending Mike to jail, they push him overboard. Mike, now acclaimed by his school, forgiven by his fathers and loved by Mary, happily paddles to the crew house.