British secret agent Harry Palmer (Caine) is assigned to investigate the kidnapping and brainwashing of prominent scientists — a job that only becomes murkier and more complex as the film progresses.

From Harry Saltzman — the producer of 007 — comes the thinking man's James Bond. Caine's Palmer is grittier, less elegant and more reticent than Bond; hence, much closer to what a spy is really like. The young actor is at the peak of his powers playing Len Deighton's working-class protagonist, and director Furie gives the film a flavorful '60s feel. Along with "Alfie," this role solidified Caine's leading man status, and rightly so.