Based on Ben Macintyre’s book, A Spy Among Friends might just be one of the best Cold War thrillers ever made. Featuring a taut script, gorgeously shot, and layered with complex emotions, the limited series details spy master Kim Philby’s catastrophic betrayal of British intelligence agencies during the 30 years he worked as a double agent for the Soviet Union, until he slipped the noose and fled to asylum in Moscow in 1963. As masterfully played by Guy Pearce, we’re reminded how Philby’s treasonous acts led to the deaths of countless Western intelligence agents and compromised untold state secrets. But the unexpected emotional power of the series comes from watching what happens when betrayal occurs on a deeply personal level, as Philby’s best friend and fellow Joe (Damian Lewis, in a knockout performance) comes to realize how he has been deceived. Equally great: Anna Maxwell Martin as an MI5 agent leading the investigation. —Michael Hainey