After leaving prison, dwarf criminal Calvin Sims joins his moron brother Percy to steal an expensive huge diamond for the mobster Walken. They are chased by the police, and Calvin hides the stone in the purse of executive Vanessa Edwards, whose husband Darryl Edwards wants them to have a baby. Percy convinces Calvin to dress like a baby and be left in front of the Edwards' house to get inside it and retrieve the diamond. Darryl and Vanessa keep Calvin for the weekend and decide to adopt him, while Walken threatens Darryl to get the stone back.

Expectant father Alan, who grew up believing he was an only child, searches for his birthmother and comes face-to-face with Russell, a brother he never knew existed and who now helps him uncover their true status as sextuplets (all played by Marlon Wayans). They go on a road trip to track down the other four siblings, but not before Alan wonders if exploring his roots was a huge mistake.

Nervous about finally getting married, a guy is forced to relive the same nerve-wracking hours over and over again until he gets things right on his wedding day.