Based on the novel by John Le Carre, The Spy Who Came in from the Cold stars Richard Burton as a dispirited, end-of-tether British secret agent. He comes in from "the cold" (meaning he is pulled out of field operations) to act as a undercover man behind the Iron Curtain. To make his staged defection seem genuine, Burton goes on an alcoholic toot and is imprisoned and publicly humiliated. Once he has been accepted into East German espionage circles, Burton discovers that what he thought was his mission was a mere subterfuge--and that he's been set up as a pawn for an entirely different operation. Though Ireland and England "stand in" for East Berlin, Spy Who Came In From the Cold has the air of authenticity throughout, thanks in great part to the bleak black and white photography by Oswald Morris. The film was condemned as incomprehensible by those filmgoers accustomed to the simplistic melodramatics of James Bond; seen today, the double-crosses and double-double crosses seem all too clear and credible.
~ Hal Erickson, All Movie Guide