The hilarity begins when professor Sherman Klump finds romance with fellow DNA specialist, Denise Gaines, and discovers a brilliant formula that reverses aging. But Sherman's thin and obnoxious alter ego, Buddy Love, wants out...and a big piece of the action. And when Buddy gets loose, things get seriously nutty.

They used to run the country. Now they're running for their lives! Two on-the-lam former Presidents of the United States. Framed in a scandal by the current President and pursued by armed agents, the two squabbling political foes plunge into a desperately frantic search for the evidence that will establish their innocence.

Frank Drebin is persuaded out of retirement to go undercover in a state prison. There he has to find out what top terrorist, Rocco, has planned for when he escapes. Adding to his problems, Frank's wife, Jane, is desperate for a baby.