Margo Martindale’s role as Mags Bennet on Justified still might be that series’ high point — but in television as in poetry, nothing gold can stay, and Mags was killed off at the end of the second season. Since then, Martindale has bounced around some CBS procedurals, but now there’s the promising news that she’s been cast on FX’s upcoming Cold War drama The Americans. She’ll play a KGB agent who relays assignments to the show’s main characters, Philip (Matthew Rhys) and Elizabeth (Keri Russell), two spies deep undercover posing as Americans. High hopes.