Narcotics detectives Mike Lowrey (Smith) and Marcus Burnett (Lawrence) have been assigned to a high-tech task force investigating the flow of designer ecstasy into Miami. This leads them to a conspiracy involving a vicious Kingpin (Molla), whose ambitions have ignited a bloody turf war. Mike and Marcus' working relationship is threatened when Mike develops feelings for Marcus' sister Syd (Union), and unless they can separate the personal from the professional, the case and Syd's life are in danger.