Breach

Somber true story follows ambitious FBI agent Eric O'Neill (Phillippe), who's planted by tough boss Kate Burroughs (Linney) as the new assistant to veteran agent Robert Hanssen (Cooper). She says the bureau is worried because Hanssen is a perv, but he's actually been selling info to the Russians and the feds want to catch him in the act. Hanssen starts getting suspicious, which ratchets up the tension, but there's never any clear idea of why he turned traitor, although Cooper is a creepily effective enigma.