‘A man who played about on the fringes of the Black Market, who had fought for Sinn Fein, who lived by his wits – and who finally became dangerous to somebody and was knocked over the head in the blackout. It may prove to be a sordid story, but I certainly find it an interesting one.

’During a stroll through Regent’s Park, Bruce Mallaig witnesses two men acting suspiciously around a footbridge. In a matter of moments, one of them has been murdered; Mallaig’s view of the assailant but a brief glimpse of a ghastly face in the glow of a struck match.

The murderer’s noiseless approach and escape seems to defy all logic, and even the victim’s identity is quickly thrown into uncertainty. Lorac’s shrewd yet personable C. I. D. man MacDonald must set to work once again to unravel this near-impossible mystery.