Kevin Whately is on our screens twice in one week. First he’s back as Inspector Robbie Lewis in four new episodes of the hit drama (starting Sunday, March 22 on ITV1). Then viewers will see him in a totally different role – as himself. For the Tonight documentary strand, Kevin investigates a subject close to his heart – dementia (MOnday, March 23, ITV1). His mother Mary, now 83, was diagnosed with Alzheimer’s disease eight years ago and recently he had to make the difficult decision to put her into a nursing home.

How did you come to present a programme about dementia?
“I met reporter Morland Sanders, who works on the Tonight show. It turned out his brother Jonathan was the geriatrician who diagnosed my mother. We talked about how Tonight should cover the subject, then he phoned and asked if I’d front it.”

Is your mother in the programme?
“Sadly her condition is so advanced that she’s not able to take part in the programme. But I feel passionately that more needs to be done to raise awareness about dementia. I’m interested in care homes.”

It’s an emotive subject. Do you think with Terry Pratchett and Fiona Phillips’ dad that we will be less afraid to talk about it?
“While we were filming, John Suchet came out and said his wife Bonnie has Alzheimer’s, so we interviewed John. He made the point that everyone is at the stage that cancer was 40 years ago – people talking about it in hushed tones and referring to it as the Big C. John calls it the Big A. He doesn’t like to call it by its name because he hates it so much. It needs to be brought out and talked about, because such huge numbers of us will be or are already affected by it.”

What stage is your mother at now?
“She’s gone through the anger and aggression and is much calmer now. She’s in a permanent state of forgetfulness. She has some long-term memory, but she has to process any new information through the past. Sometimes I’m her dad who died in her 30s. You have to throw yourself into her reality. You can’t impose your own logic, as it doesn’t work. You have to work out where she is and try to understand.”

Do you find it distressing?
“It is very distressing yes, but it’s something you get used to. I call it a Happy Groundhog day – you work out what she’s happy talking about and just go round and round. It might seem like lying, you do have to do a certain amount of acting, pretending you haven’t heard it before. But it’s the best way, and once you relax into it its all right.”

Is it childlike?
“Very childlike. My granddaughter is two, and hasn’t quite learned how to string a sentence together and there’s something very similar in the way she and my mum speak.”

Do you think there should be more dramas and documentaries about Alzheimer’s?
“The first time I was approached by the Alzheimer’s Society, I did a film called Dad for Comic Relief. Jean Haywood played my mum, who was hospitalised with dementia, so my dad, played by Richard Briers, moved in with me and Sinead Cusack and our kids. My mum was diagnosed in 2001 and this was 2005. The public are relating to it more and more – there was also an award winning storyline in Corrie with Johnny Briggs.”

On a lighter now, how was it going back and filming the new series of Lewis, which starts the same week as the Tonight film?
“We’ve been doing this off and on for 20 years, so it’s like a home from home.”

In episode one, Lewis gets set up on a date with a woman who turns out to be a suspect…
“That’s the kind of thing Morse did. I don’t mind him having flirtations, as long as he doesn’t get too involved as then it just becomes a soap!”

Are there any emotional scenes for you two this time?
“In the second film, there’s a lot about my wife. Laurence happens to discover whodunit almost by accident, and he’s in a bind about whether to tell me. She was killed by a hit and run, but they never caught the driver. Laurence tells me and it’s my big emotional scene.”

What was your favourite episode?
“I love the second one as it’s by Alan Plater, my favourite writer. But also episode four is a fab script by Guy Andrews and starring Joanna Lumley, David Hayman and Simon Callow. It’s about a Sixties group that Lewis was a big fan of when he was younger. They were based on a Welsh band called 10 Years After, which I used to love when I was young. But then they evolved into more like Fleetwood Mac.”

Are you and your co-star Laurence Fox working on a script for Lewis?
“We happened to be standing under the Bridge of Sighs next to where Halley of Halley’s Comet did his stargazing, and Laurence and I started pooling ideas. Every now and then we go out for a drink and take it further on. We’ve got loads of ideas, but whether they will all gel into one remains to be seen. The main difficulty these days is building up five crises to fit in with ad breaks.”

Who would be your ideal cast?
“I’ve got a huge list at home, but I’d love to work with David Warner and Sheila Hancock.”

What was it like working with Laurence and his father James Fox, who appears in episode one as a prime suspect?
“It was hysterical for us because Lol is so anarchic, funny and chaotic but always comes up with a great performance. James is more like me, he’s a grafter, and really works on his performance. They’re chalk and cheese. I think he really enjoyed working with his son. It was a joy to watch them as they’re really affectionate with each other, and they make each other giggle. It must be odd to act with your father or your son. Lol was really nervous. I thought his dad would have a calming influence, but he was just as naughty as ever!”

What’s your relationship like with Laurence off set?
“We do a lot of joshing. Well, he does a lot, and I just have to take it. Oh all right – I do a bit too! It’s really joyful. He keeps the crew happy. His baby was around a lot early on. Little Winston, he’s superb. Billie Piper’s around a lot too – the whole thing has always felt like a big family. My own kids used to come all the time when they were little, but now they’re grown up they’re not so interested.”

CLICK here to exclusive photos from the set of Lewis.

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