It was announced in July that the television movie would focus on Sam Axe (Campbell) and his final mission for the CIA.
The actor told Entertainment Weekly that Axe will go rogue while on assignment in the Colombian mountains.
"[Sam] sees some events go down that change the initial plan," he revealed. "He takes matters into his own hands at great risk to himself and others with a small group of misfits to try to right a bad situation. It's a David and Goliath thing."
Campbell added that the film, directed by Burn Notice star Jeffrey Donovan, will explore the "mature side of Sam" and will introduce a recurring element for the show's fifth season.
"[People] should watch it because that's the only way they're going to get the whole story [of season five]," he explained. "There is possibly a character and story elements that will linger forward, and not in a good way. Something from Sam's past might come back to haunt him."
The two-hour Burn Notice prequel will air in Spring 2011 on USA.