Doll & Em on putting their friendship to a screen test

Famous dad: Satirist John Wells

You Know Her From: The IT Crowd and Bridget Jones’s Diary

Emily and I have been writing together for a very long time and we have been friends forever. Initially, the writing was really just an excuse to be together – there was only so long we could justify to boyfriends/husbands that I needed to fly over to America, again, to be with Em when she was making a film.

But then we came up with this idea of a power struggle between two people who really love each other, and Doll & Em took off. Calling it by our own names was the director’s idea, but hopefully people will understand that we’re playing versions of ourselves.

When we were about six or seven our families went on a skiing holiday together. I remember really enjoying Emily’s company. As teenagers, when we did stuff, things always seemed to go wrong. I remember Em wearing a pair of jeans that she wanted “acid-washed”; unfortunately she was wearing them while I was doing it and she burned her bum. We were always laughing.

After we left university – Em was at Oxford and I was at Manchester – Em started acting before me. She was in one of her first jobs on TV, and I was working on a newspaper diary page. I never had any stories so I asked Em if I could write something about her. And, of course, they changed it and it got her into trouble. The next day I came in to work with a red, swollen face from crying, saying they had to retract the piece or it would ruin my friendship. They did, even- tually, but it was awful. Then soon after that [in 1998], my dad died and Em was brilliant. Deep down, I feel Doll & Em is a love letter to our dads, because we adored them.

For me, Emily’s an incredible treat. She’s funny, clever and kind, really hard working. Just adorable. And she was brave to want to do this project with me because she has such a successful career – it was a much greater leap of faith for her than for me.

We joke that here we are, making this show that’s all about friendship, so what if we have a massive row? But it hasn’t happened yet.

I moved to New York last August – my husband’s American – and now we’re living one road away from Emily. Until then it was just me and Em. Now suddenly you’re bringing husbands and children into it. Fortunately, it really works.

When I see my daughter Elsie and Emily’s son Sam giggling and having just as lovely a time together as Emily and I did at that age, it moves me. It’s the point of everything, really.

Emily Mortimer

Age: 42

Famous dad: Writer John Mortimer

You Know Her From: Match Point, The Newsroom

I’ve known Dolly all my life. Our fathers moved in similar circles and our mums tell us that we “met” as babies, but my earliest memories of Doll are playdates at her house in Kensington. I was impressed because she was naughty. I was the oldest sibling in my family so I was typically well behaved and boring, caring way too much what other people thought.

Dolly was a younger sibling and naughty as hell, in the most charming way. I was enchanted by how fearless and funny and up for life she was.

It was when Dolly’s dad died that we got really close. I think we started to realise how much we shared in our relationships with our dads. They were both such important figures in our lives and we loved them so much. I feel they both looked at the world with forgiving eyes and that’s just so comforting to be around.

It was only as we were writing Doll & Em that we realised, in some way, we were being each other’s surrogate dad. My dad always used to say there was no problem so big that it couldn’t be solved by a restaurant with nice linen cloths and a glass of champagne. We’d go out to lunch and I’d think, “There’s so many problems I want to talk to him about” – but by the time I’d been in his company five minutes I wouldn’t care. I just felt, “This is more fun than anything!” And it feels like that hanging out with Dolly.

No matter how bad things are, it’s all OK when you have someone you can laugh about it with. And say the absolute worst things to. Part of our shared humour is being able to come out with the most shameful feelings. One of the things I feel proudest of in the show is the way we outed jealousy between friends. It’s a taboo subject because one hates oneself for feeling it. Exploring that between two friends is, I hope, cathartic.

When Dolly moved to New York last year, it made me think, “How did I get through ten years without her here?” I’d never before had anyone in the same city I could just phone up in full, heaving-sobbing mode, knowing she’d pick up the phone and it would all be fine.

Now our children are best friends. They know they have to get on, because of Dolly and me, but they love each other independently of us. They get the importance of the shared history and the special intimacy it brings. All any of us is really after is that feeling of being known and understood. It’s a very, very sweet thing.

Doll & Em, Tuesday 10:00pm, Sky Living

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