Lord Ashfordly's sister Patricia Brewster is visiting her brother to present her new fiancée Ronnie Harper. Sober. While his lordship is giving an engagement party in their honour one of his guests is burgled and another one was the previous night. Lady Patricia asks her fiancée, who has a criminal record, if he knows something about it, and the police have an eye on Harper too. Harper on the other hand has both his eyes set on Gina who is not insusceptible to his charm. Greengrass is harbouring two workmen, Keith and Chas, who do some renovations around the village. Among other things they are refitting Oscar Blaketon's bathroom, and he smells a rat.