Marcus Garvey plays Keith in the sitcom...

What was it about this character that appealed to you Marcus?

Who doesn't want to get paid to play an idiot?! It's always fun to play a clown. I'm dead lucky - I get to say the punchline in a lot of scenes. That's magic!

Keith is like the kid who never grew up. Keith got Debs pregnant when they were 17, and that's when Keith's childhood is supposed to have stopped. But there is still a lot of kid in him. At one point, Keith says, 'My son Charlie loves my - I mean, his Scalextric'. Keith has a playmate in his own child!

Have you had a good time working with Daisy Beaumont, who plays Debs?

Definitely. She is brilliant. Debs has another child to look after in Keith, and Daisy plays that so well. It would be easy to become bogged down playing the controlling force in a relationship, but Daisy never does that. It's like commedia dell'arte - at any point one actor should always be unmasked and in control. That's Daisy's job in our scenes. She has to play it controlling but never bossy - and Daisy is superb at that.

Keith has some great scenes with his daughter, Ellie, too, doesn't he?

Yes. Ellie is a great character. She is like a mini-Debs. She puts up with a lot and is a lot more intelligent than her dad - as teenage daughters often are!

How does Keith regard the relationship between Lauren and Ed?

At first Keith didn't care about it, but gradually he's warming to Ed. To begin with, Keith took the micky out of Ed and called him old. Ed just rolled his eyes and gritted his teeth. He thought he'd become part of the Addams Family and just had to put up with it.

What has changed then?

Now Ed sees that Lauren is so wacky because she comes from this very warm family. That warmth is reflected in our relationships off camera. It's such a lovely bunch of people, and there's a great atmosphere on set. We all get on so well.

Why have viewers been so taken by You, Me & Them?

Because, like the characters in this show, everyone thinks their family is weird. Growing up, you'd look at your mates' families and think, 'Why can't we be sorted like them? They always have crispy pancakes on a Friday night.'

Does that continue throughout our lives?

Yes, it never goes away. Now I'm looking at mates getting married and thinking, 'I'd like their three-bedroom house with a conservatory!' That's why this show is so popular - because people can really relate to it.