When $100 million of seized heroin is stolen from the Miami Police lockup, Detectives Lowrey (Will Smith - 'Men In Black') and Burnett (Martin Lawrence), Miami's most mismatched cops, are called upon to solve the case before the FBI close their department. Julie (Tea Leoni) is their only lead to the case, but will only speak to Lowrey. As he is not around when she calls, Burnett impersonates his cool, slick partner. A hilarious role reversal begins in order to retain her trust. From then on, it's a race against time as the trio dodge the mob, and retain their charade while putting pressure on every low-life in Miami's underworld to track down their man.