S13:E01 - The Sword of Guillaume

Barnaby is not convinced about Mayor David Hicks' plans to revive an annual trip to Brighton, suspecting his proposal to buy coastal land there, is rather a fraudulent scheme. Naturally, he joins the trip, but during their time in Brighton, a hated property developer (Tim McInnerny) is beheaded on a ghost house ride, prompting Barnaby to team up with his cousin to determine whether the developer's renters, the mayor, a gloomy reverend (Mark Gatiss), or the lady of a large estate are responsible, and soon discovers a hotbed of jealously, debt, lies and more, conceal a far darker secret.