AN interesting life is a pretty big understatement when it comes to Leslie Grantham. Enlisting in the British Army as a teenager, he was a convicted murderer by the time he reached his 21st birthday. Born just after the war, Grantham was sentenced to life imprisonment following the killing in Osnabruck in which a bungled armed heist in a taxi went horribly wrong.

But he went on to turn his life around in prison, enrolling in drama classes and befriending other actors inside.

The 63–year-old became a household name as one of the most celebrated soap characters of all time – ‘Dirty’ Den Watts before leaving the EastEnders cast for a second time in 2005.

Grantham was at the centre of an online sex scandal just before his departure from the soap when a Sunday tabloid printed pictures of an explicit webcam conversation from his dressing room.

Now he’s reinvented himself once again – as an acclaimed stage actor in another much-loved BBC show about the Home Guard.

“I wanted to do something where the audience are not being short-changed,” he tells me.

“I’ve been offered the jungle, Strictly Come Dancing and all the others. But I don’t want to sit in a house full of people I don’t like for months, I don’t want to learn to ice-skate and I don’t want anyone rummaging in my loft looking for hidden treasure.

“Twenty years ago if I was in conversation with you we’d have said that British TV is the best in the world. But now America has really taken it on with the likes of CSI, The Wire and 24.

“I did some theatre when I first left drama school, but then I got hijacked by TV. When I left EastEnders the second time, I did make a concerted effort to do more theatre and I keep getting great offers. When you’ve done Den Watts, there’s not a lot left on TV.

“British audiences are fed up with being told what they should watch. We’re not well served with what we have on our screens and it makes you wonder what you pay the licence or subscription fees for really.”

His distaste for modern British television has led to a number of stage roles with the latest tour of Dad’s Army Marches On proving a huge hit with audiences around the UK.

The show, in which Leslie plays Private Walker the role made famous by Jimmy Beck, now has a cult following just like the Jimmy Perry and David Croft sitcom which was a parody of life in the Home Guard in the Second World War.

“Some of the places we go to, people are now dressing up!” he laughs.

“You have to walk out and try not to take any notice of an audience dressed up in army gear and full of laughter. It gets a bit like a pantomime at times!

“You’ve got mum and dad and grandma and grandad and it’s nothing offensive, it’s all tongue in cheek and good fun. I think audiences have got a real affection and affinity for this, just like the TV show.

“I like that, it’s good. I’m not going to lie and say I’m a lifelong fan but if it’s on I always watch it. Well it’s better than Cash in the Attic isn’t it?”

• Dad’s Army Marches On is at Ferneham Hall in Fareham from Thursday to Saturday.

Tickets are available by calling 01329 231942 or visiting fernehamhall.co.uk