Harry has evidently gone up in the world since he sold Woodcote Park because he now drives a Jaguar XJ6. He is planning to start a security business from offices at a canal basin by the Trent but his bank manager, Mr Statter, refuses him a loan. Ken, Rocky and Laura have moved from Royal Hill and are temporarily working out of a very tacky caravan.

Ken is on horseback, investigating water pollution and dead fish at a quarry near Dornford Hall for his clients, the peremptory and patronising Dr Sinclair Lewis, and Simon, a member of an ecological pressure group. They believe that the pollution is due to the dumping of toxic waste, possibly solvents used in the production of ceramics. Suddenly an air-rifle pellet is fired at Ken's horse, throwing him off. A beautiful Polish woman, Irena Tadeusz, who lives at Dornford Hall, rescues him. She tells him about a friend, Brigadier Charles, who was beaten up in a robbery. She is very frightened, so Ken offers to do a free survey with a view to fitting an alarm - this will be an excuse for him to snoop around and may lead to a bit of business for Harry's new security company.

There are reports on the news of a spate of antique burglaries from country houses. It is also reported that Brigadier Charles has died from his injuries. When Ken goes back to do his survey he snoops round the house and finds the tape recorder that he was dictating into when he was thrown from his horse. As he is leaving, Irena gives him a present: a tin containing a cake. Much later he discovers, at the bottom of the tin, a wad of photographs of antiques that were stolen in the robberies. Having recognised the Brigadier's antiques in the photos, he realises that Irena is involved in the thefts. He searches the quarry and finds an underground smelting works, and shelves full of stolen antiques and innocent-looking ceramic pots containing silver ingots. Irena's boyfriend, Andrew, attacks Ken, but the police arrive in the nick of time. It turns out that Irena had been photographing houses in detail to help Andrew to carry out the thefts. However she was now desperately trying to stop him because he had begun to hurt people - and to enjoy it.

Laura is singing with a band in the local pub, The Drum. Angus, who manages the band, tries to get her to join them full-time. Laura is thinking seriously of leaving Ken and going to London to sing professionally. Angus and Laura take part in a talent contest. However the talent scout wants the band but not Laura.

Mr Statter, the bank manager, eventually changes his mind and gives Harry his loan. Harry and Ken decide to go into partnership, running Crawford Boon Security (CBS), with Ken running the investigation side of the business and Harry acting as a security consultant. Ken plans to live in a yacht moored in the canal basin next to the CBS office.