John Nettles was moved to tears while filming the new episodes of Midsomer Murders.

He explains: "Sam Hazeldine comes into the series, playing Cully's boyfriend Simon. When he first arrived on the set, it made me cry a little bit, because Sam looks so like his dad James and he's got the same pitch of voice as well.

"I'd known Jimmy Hazeldine since he was a kid and we started out together with Alun Armstrong. He was coming to a golden period in his career and doing wonderful stuff when he dropped off the twig. It was a great, great shame."

However, John is looking forward to working more with Sam as the romance develops between Simon and Cully.

"Barnaby initially hates it when Cully meets someone. It's traditional Middle England attitude - no man is good enough for my daughter. But when Simon proves a dab hand at laying the patio he comes round to him. The way to the father's heart is through the patio - isn't that so beautifully English!

The new films also see John fulfilling a dream, playing guitar on screen, when Barnaby investigates death and mystery amongst an ageing rock band, who reunite to play at the Midsomer Rocks festival.

"I got to play the electric guitar which is a schoolboy dream. The playing wasn't fantastic but the feeling was pretty good. We went to Bedfordshire to film the rock festival at a rhythm and blues concert, and there was my generation, all fat-gutted and thinning hair, with their kids all bopping along to the music. It was divine."

Ten years of Midsomer Murders has seen Barnaby investigate more than 100 killings, each of them different and occasionally bizarre.

"There's something warped about the nature of our writers, they come up with extraordinary ways of killing people. There's nothing to compare with the one where Oliver Ford Davies was pinned down by croquet hoops on his lawn and catapulted with bottles of his vintage wine while his wife directed proceedings from an upstairs bedroom. It doesn't come more baroque than that!

"In a future episode, Barnaby is set up in what looks like a sexual peccadillo. A photograph surfaces in which he is kissing a woman. The woman is played by Liza Goddard who was my girlfriend in Bergerac and it was lovely to see her again. She's worn considerably better than me.

"One of the joys of the series is working with stars like Joss Ackland, Richard Briers or Richard Todd. I'd like to get Michael Gambon and Greta Scacchi in, and I think Roger Moore has expressed an interest in playing a dead body. I'd be hugely pleased to see him. I've loved him since he drove that Volvo in The Saint."

John admits to being a fan of other TV police series and detective fiction.

"I love forensic shows and especially CSI, where the nature of the storytelling is wonderful as is the casting. I'd watch David Caruso in CSI: Miami for ever. I also like books by Kathy Reichs and Patricia Cornwell. They're very pacily written, but if you set out your stall to do grizzly things and exotic deaths it's hard to keep topping it the next time."

John says: "Midsomer Murders has separated me from my wife and my dogs as I live down in Buckinghamshire in the week and get attacked by the dogs at weekends because they don't recognise me. But I can't remember what life was like before. It's just a life that's altered but very happy it is too."