There's not a lot going in 2 Fast 2 Furious. It's a pretty vacuous film involving one-dimensional characters with a preposterous plot. That doesn't mean it's not entertaining, but make sure you check your brain at the door.
Brian O'Connor (Paul Walker) is an ex-cop who hustles Miami drag racers for spare cash. Roman Pierce (Tyrese Gibson) is an angry ex-convict on an electronic leash who blames O'Connor for his predicament. They're both supposed to work together in a sting operation to capture a ruthless drug dealer, whose methods of torture include allowing a rat to gnaw at a man's stomach.
The actors are mostly good-looking people but the direction is so poor that they appear to be talking to themselves in a daze (i.e., unable to project the other characters off-screen). This results in a slight incongruity whenever there's dialogue involved, but since the movie is about really fast motions (in different forms of vehicles) it doesn't detract too much from the film.
Even though 2 Fast 2 Furious is fast-paced and keeps the action going, at the end you'll feel as though you had just eaten a full meal and can't understand why you're starved. Worth renting if you're bored.