Mike Lowrey and Marcus Burnett are partners on the Miami PD's Tactical Narcotics Team. Although they used to be good friends, things have been going down hill and the two are keeping secrets from each other. Mike's secret is that he is dating Sydney Burnett, Marcus's sister and DEA paper-pusher. Marcus's secret is that he has requested a transfer away from Mike. While they attempt to work through their problems with each other, they must also try to stop the flow of ecstasy into Miami. The leader of the ecstasy trade is Hector Juan Carlos "Johnny" Tapia, a Cuban drug kingpin. Tapia is trying to control not only the ecstasy trade in Miami, but the ecstasy trade in all of the USA. Things really heat up when it is discovered that Sydney is actually working undercover trying to infiltrate Tapia's group in order to bring down the Russian mafia boss Alexei.