Dudgeon will play the character of John Barnaby, a cousin of Nettles's character Tom Barnaby. He will make his first appearance in the 10 February episode, and then again in the 14th series, which will be shot from July. Having appeared in more than 80 episodes of Midsomer Murders over 13 years, Nettles is now retiring.
Producer Brian True-May said that he looks forward to their "new Barnaby tackling more murder and mayhem in Midsomer". He added that the brand of Midsomer remains very strong and he is confident of its continuing success.