The Barnaby-Troy partnership is about to come to an end, as Troy has passed his inspector's exam and is moving on. However, the murderers of Midsomer go on piling up the bodies.
Joyce Barnaby gets trapped in a fallen canal tunnel, and in getting her out seven skeletons come to light in a hidden chamber. Meanwhile, two local tearaways are shot dead in the woods at Midsomer Worthy, and a tramp called Tom is accused of the killings. While Troy looks into the shootings, Barnaby wrestles with an old mystery. And although six of the skeletons found in the tunnel date from the 18th century, one is much more recent.
A craft centre in the old mill at Morton Fendle is losing money. Several locals have invested in the business and believe they have been swindled by Alan Hollingsworth, the man behind it. When Hollingsworth's glamorous wife Simone goes missing, Barnaby believes she has been kidnapped and puts Hollingsworth under observation. However, Hollingsworth evades the police, carrying a bundle of cash, and a woman neighbour who follows him to his rendez-vous is killed in a bizarre road accident. Then Hollingsworth is found dead, and Simone turns up alive. Barnaby guesses she and a friend faked the kidnapping, but he can't prove it.
The body of Agnes Gray, a woman who loved only animals, is found in the river - but she did not drown. And then her cousin Esslyn Carmichael is tricked into killing himself on stage during an amateur production of the murder mystery Amadeus.
Barnaby has to get to grips with clues which include adultery, dramatic ambition, stolen religious art, and large donations to animal charities, before unmasking a killer who proves to be mad.
Meanwhile, love begins to blossom between Cully Barnaby and Nico Bentley, one of the cast of Amadeus...