David Callan, an outcast secret agent, revisits his former department for talks. The ‘Section’ exists to deal with undesirables, people in ‘Red Files’. Its supervisor, Hunter, offers to reinstate Callan but first he must carry out a killing. He must do this within one week, without help and without asking why. His target is Rudolf Schneider, a German businessman with whom he’s already acquainted; Hunter has engineered Callan’s placement in a company in the same office building. Callan suspects Hunter’s offer isn’t genuine and takes a liking to the extrovert German, as they share an interest in war gaming. Nevertheless, he orders an illicit gun from Lonely, an old criminal associate. Meres, a Section operative, keeps watch on Callan. Needing to know why Hunter wants Schneider killed, Callan searches the entrepreneur’s office and home, finding he’s been selling armaments made by a Japanese firm, noguchi, to Indonesia, where they are being used to kill British troops. He specifically asks Lonely to get him a Noguchi Magnum .38 calibre revolver for the forthcoming execution.