But He's a LORD, Mr. Callan

Caroline Fielding (Ann Bell) is being blackmailed with photographs of her husband in compromising positions. John Fielding is a close friend of the American president's nephew, and it is Hunter's task to stop the suspected blackmailer, Lord Lindale (Donald Hewlett), from selling the negatives to the Russians.

Callan is visited by an ex-colleague Miller (Gerald Flood) who has just been released from prison. He wants Callan's help to obtain some money belonging to a Lord, but Callan refuses to help when his suspicions are aroused by Miller's claim to have followed Lonely there. Later, Lonely tells Callan that Miller had tried to follow him, but that he lost Miller easily, following him in turn to various gambling clubs, one of which, it turns out, Callan has been made a member of by persons unknown.

When Meres asks Hunter about Callan's involvement, Hunter tells him that Lindale may need killing, but the Section cannot be involved. Callan attends the club, where he meets Miller, and is introduced to Lindale and Caroline. Lindale invites them back to his flat for a game of piquet, where Callan eventually makes a spectacular win.

The following day, Callan and Lonely break into Lindale's flat and find the photographs in the safe, leading Callan to the conclusion of blackmail. Having been invited to Lindale's country home, Bootwood Hall, Callan arrives to join the gambling party consisting of Lindale, Miller, Caroline and Colonel Hunter.

That evening the card game commences, and carries on to morning, with Lindale down eighteen thousand pounds to Callan. Once alone, with Callan, Lindale demands his I.O.U.s back at gun point, then goes off to find them, locking Callan in the room. On his return, Callan appears to be missing, but from his hiding place he fires a single shot and kills the Lord.

Callan finds the negatives on the body and hands them to Caroline to burn. To clear himself of the murder, Callan insists that Hunter back him up with his story that Miller fired the shot. Hunter has no choice, as Callan still has the prints in a safe place.