Eric Walsh is found strangled in the car park after the North Brunton Masonic Lodge Ladies' Night. Walsh being a ladies' man, suspicion falls on many cuckolded husbands - one of whom, Peach is entertained to discover, is the Master of the Lodge. Equally suspicious is Cartwright the loan shark, Afzaal the waiter who seems to have something to hide, O'Connor the Irish Republican who has cause for vengeance ... and of course Chief Inspector Tucker, Peach's boss. After all, he too is a mason and, as Peach will never let him forget, masons are four times as likely to commit a serious crime in the area as anyone else.