"A decorous, solidly smart thriller whose menace maintains a sort of low, steady hum."
★★★★ Leah Greenblatt, Entertainment Weekly

"Cumberbatch, emaciated and shaven-headed, exposes the slightly alien being he always contains and the film gears up considerably in emotional impact. This is Cumberbatch's best espionage film, then, after Tinker Tailor Soldier Spy."
David Sexton, New Statesman