The Ipcress File (1962)

A missing scientist sends an unnamed British operative through an intelligence world full of class resentment, office politics and unreliable explanations. The sardonic voice is central to the appeal: this employee notices the food, the paperwork and the people giving orders. Begin here for Deighton's early spy novels, allowing for a deliberately disorientating mystery and the attitudes of its 1960s setting. The film's Harry Palmer name is not the novel's narrator's name.