Undercover-cop dramas are only as good as their actors; what makes them compelling is watching righteous people immerse themselves in dirty roles. I've never exactly followed Radcliffe's work, but he is terrific here, comparable even to Leo's work in "The Departed" and Roth's in "Reservoir Dogs." Exploits the current state of American politics? Yes, why shouldn't it? Deadly serious? Of course, why wouldn't it be?