Readers of advanced years like me will almost certainly remember the bow-tied figure of Edgar Lustgarten, star of any number of ‘True Crime’ B movies which were an integral part of a visit to the cinema, or ‘flicks’, when we were young. Some of us also remember his catchphrase when describing the downfall of a murderer, if only because it was a favourite of The Spectator’s one-time political columnist Alan Watkins: ‘It was then that he made his first big mistake.’