About to star in the second series of Line of Duty, Keeley Hawes discusses falling into fame, a second marriage and OCD

“Hello darling!” A tall, slender woman with long blonde hair waves enthusiastically at Keeley Hawes, who looks bemused then does a classic double-take. “I didn’t recognise you!” Hawes calls, going over to exchange hugs. “You look a lot better than the last time I saw you!

“Covered in third-degree burns,” Hawes explains briefly, returning to her seat.

We have met in a bar at the Soho Hotel to discuss the upcoming second series of the BBC’s bent copper drama Line of Duty. Hawes takes the starring role of DI Lindsay Denton, an apparently incorruptible officer who is suspected of leaking information that leads to the grisly death of three colleagues in an ambush (including the aforementioned blonde, who is burnt to death).

It is absolutely brass monkeys outside but Hawes, undeterred, has arrived bare-legged, her feet encased in very chic blue strappy Yves Saint Laurent heels. “They were a Christmas present from myself,” she says. Otherwise, she is all in black, with floppy three-quarter-length Theory trousers, a gauzy Topshop blouse and a Diane von Furstenberg jacket. She is also wearing a good deal of blingy jewellery, including a gold snake bracelet with diamonds in the head, bought for her by her husband, Matthew Macfadyen, and a ring that was another Christmas present. Her features are classically beautiful: she has large, heavy-lidded eyes, a dainty nose and pale skin offset by a slash of scarlet lipstick. And she, too, looks a lot better than she does on screen. As the sinisterly enigmatic DI Denton, when she isn’t having her head shoved down the loo by vengeful co-workers, she sports flat hair, dark circles under her eyes and a pasty complexion, not to mention some extra poundage. Did she put weight on for the role? “I didn’t bother keeping it off,” she says. “After we filmed it, I went in to do some dubbing and one of the sound guys said “God, that’s really something! It’s a bit like when Charlize Theron did Monster!” But Theron had prosthetics and had put on about three stone and shaved her eyebrows off. This was just me with no make-up on!” She roars with laughter.

“It’s the only job I’ve ever done where I’ve walked into make-up in the morning and they’ve said, ‘Yup, that’s absolutely fine’. It was actually really liberating. But it is weird in this business because you do watch yourself ageing on screen.”

The other evening, she says, she was flicking through the TV channels and happened on an old episode of The Vicar of Dibley, which she had filmed seven years ago, just after the birth of her third child, Ralph. “It feels like five minutes ago, but I was looking at it thinking, ‘God, I looked all right!’ You never appreciate what you’ve got till it’s ten years too late.” All the same, she doesn’t try to hold back the years artificially. “Not in any way. Look at my forehead,” she says, wrinkling it up to demonstrate its mobility. Is avoiding Botox a matter of principle? “No — I’m thinking about it,” she says. “But I can’t see how it would help me in my line of work. I couldn’t have played this part if I’d been Botoxed.”

Hawes has been an on-screen regular since the age of 9. The daughter of a London cabbie, she persuaded her parents to stump up for the fees to the Sylvia Young Theatre School, which was on the same street in Marylebone as her council flat, because she enjoyed being in school plays. “I don’t think I had any ambitions for fame, I just loved drama.”

Hawes first came to critical attention through her roles in Dennis Potter’s Karaoke and Cold Lazarus, and has continued to make credible choices ever since. Her repertoire is impressively versatile. She has starred in numerous period dramas, including Wives and Daughters, Tipping the Velvet and the re-launch of Upstairs, Downstairs. Her comedy appearances include The Vicar of Dibley and, latterly, Ambassadors, alongside Mitchell and Webb, while her role in Line of Duty is the latest in a series of hit contemporary dramas that includes Spooks, Ashes to Ashesand The Tunnel. Her most recent theatre outing, in the premiere of Clive Exton’s farce Barking in Essex, had her playing against type as a tough, tarty, perma-tanned Essex girl. Just before Christmas, however, Hawes abruptly left the production, reportedly after rows with Sheila Hancock, who played the family matriarch, though no official explanation was ever given.

So what really happened? “Oh, no, no, no, I can’t! I’ve made a statement and I have to stick by it,” she says, bursting into a peal of nervous laughter. “I left the show. It’s not something one does lightly. But there was no alternative.” It meant that she got to spend Christmas at home in Twickenham with her three children, Myles, 13, Maggie, 9, and Ralph, 7 — unlike her husband, who is starring in the West End comedy Perfect Nonsense, as super-butler Jeeves to Stephen Mangan’s Wooster, and only had one day off.

Is Macfadyen Jeeves-like at home? “He’d hate it if I said he was, but he likes order, which is great because you couldn’t live with me if you didn’t like it,” she says. “I thrive on things being orderly. I’m very tidy and very clean. Very clean,” she repeats emphatically. “In a life which can be quite complicated, the house has to be ordered. And having three children as well — I don’t know how people cope with a mess.” I’m not sure how people with three children cope without a mess, I say. “Oh no! I’m training them all up,” she says, with a slightly sinister chuckle. “It’s good for them.”

She, like Kirstie Allsopp, revels in a bit of ironing. “Ironing is awesome! I was ironing just last night. There’s something very satisfying about it.” How about dusting and polishing? “Yes, I love it. I love the environment to be as nice as it possibly can be.”

Consequently, she’s also a ruthless declutterer. “I went to the charity shop just this morning.” Her children are regularly made to clear out their toys. “My daughter is excellent at it, my sons less so. Father Christmas doesn’t come to houses where there are too many toys.” Doesn’t he? “Nope. He just flies straight over,” she says, with a meaningful look. “I forced Matthew to have a book purge the other day. He does love books but I got some boxes together and said, right! And I stood there with him. I’m desperate to buy him a Kindle and put everything on there.”

Naturally Hawes’s own wardrobe is colour-coordinated and pared down to the essentials. “The holy grail is a capsule wardrobe, though I haven’t quite achieved it” — but it’s not for want of trying. “I read a brilliant tip about putting all your clothes on the hangers one way, and when you wear an outfit, you put the hanger back the other way. Then, when you get to the end of two months or something, you’ll see all the clothes you haven’t turned around, and you can get rid of them because you won’t miss them. Isn’t it brilliant? And simple, and you have no excuse. I’ve never missed a thing that I’ve got rid of.”

She employs a cleaner once a week, but last week she cleaned alongside her. “We were trying out the merits of a feather duster,” she explains. “My mother-in-law bought me a beautiful ostrich feather duster for Christmas.” Hawes’s fetish for cleanliness even extends to the family dog. Nana is a Coton de Tuléar, an exotic breed from Madagascar, and was chosen because she doesn’t moult — partly because Hawes and Macfadyen are allergic, and partly, Hawes admits, because she doesn’t want dog hair all over the house.

“Oh dear, am I sounding completely insane?” Well, possibly a touch OCD, I suggest. “There’s nothing wrong with that — it gets a very bad press,” she jokes. “I think it’s because I couldn’t cope with it otherwise; if I worked very hard and then had a day off and had to spend it trying to organise everything.”

Hawes and Macfadyen met on the set of Spooks 12 years ago and fell madly in love. Somewhat unfortunately, Hawes had only just tied the knot with her long-term partner, cartoonist Spencer McCallum, father of her son Myles. Briefly, the glamorous pair found themselves in the eye of a tabloid storm, but that was weathered long ago, and relations between them all are hyper-civilised. “My son was very little, so the situation as it is, is all any of them have ever known.” McCallum is, says Hawes, “part of the family, really. He’s a sort of uncle to the other two. He’ll come and pick them up and take them off for a pizza.” She says she feels “very proud” of her ex. “I thank my lucky stars that he’s been so amazing.”

With both parents currently much in demand, keeping family life on the rails is a constant juggling act. “Line of Duty is the only time I’ve ever been away for work and had to take a flight. Otherwise the furthest I’ve really been is Wales, and then I basically commuted. Matthew’s been all over the world, and it’s me that stays.” She insists she doesn’t mind. “I love working, but I couldn’t cope if I felt really guilty. And I love my children and I want to see them.”

Weekends are dedicated family time. “We’ll usually go to Wagamama on a Saturday, and then have a walk by the river. And Sundays are pyjama days, and Matthew cooks a roast. He is an excellent cook, he can turn his hand to anything. He’s Jeeves-ish in that way. And I like washing up, so that works very well.” Her secret indulgence is “crap telly” of the sort she’d never do herself. “I like Come Dine With Me, or The Hoarder Next Door, my ultimate nightmare,” she says, with a delicious shudder. “I find it fascinating.”

At which point her publicist comes in to announce that our chat is over. “I’ve made myself sound like a total lunatic, an obsessive compulsive cleaning freak,” Hawes tells her. “Well, that’s what I am!”

Keeley Hawes stars in Line of Duty on BBC Two, starting Wednesday February 12 at 9pm

My perfect weekend

Night in or night out?
Night in

Tesco or Abel & Cole?
Matthew likes Abel & Cole

E-mail or snail mail?
E-mail

National Gallery or Natural History Museum?
Natural History Museum

Small screen or big screen?
Small screen

Juice detox or fasting?
Juice detox

Novel or poetry?
Novel

Sun or ski?
Sun

Chat show or reality TV?
Come Dine With Me

Skinny jeans or tracksuit bottoms?
Skinny jeans

I couldn’t get through the weekend without . . .
bleach. And Dettol wipes. They’re the answer to everything