Samantha Morton wants to get one thing straight. She does not think of herself as a film director. Has no aspirations in that area. This is a one-off. Just something she had to get out of her system. For half her life, she's wanted to tell this story, needed to tell this story, and now she's done it, so she's happy to leave it at that. The Unloved is a bleak and beautiful drama about a little girl in a care home. The girl, Lucy, just happens to have ice-blue eyes and look how we might imagine the young Sam to look. She is rejected by her mother, beaten by her father, thrown into a Nottinghamshire home where she gets into trouble with the police, runs away time and again, and witnesses yet more abuse. All the time, she is looking for one thing: love. Somebody to love her, somebody she can love. Everything in the film is seen from Lucy's perspective. We stare up towards an adult waist and the terrifying prospect of a belt being unbuckled, sounds are heightened (birdsong, a running bath, the swish of the belt), and elements of the story are left unexplained because Lucy simply does not know, for example, why her mother can't look after her. She could be selfish, physically ill, mentally ill, or all three. The Unloved is Ken Loach on downers. It offers little in the way of hope or consolation - and it is a brilliant depiction of aloneness.
Morton, now 31, was 16 when she started storyboarding the film. She was living in a hostel for the homeless when she read an article about a young prostitute in Nottingham and realised this was somebody she had known in care. Years later, she read about two other girls she'd known who had also become prostitutes and had been murdered. The reports had a huge impact on her. She wanted to tell their stories, and her own story, and create something fictional, all at the same time. She started to write scripts, but rejected them as rubbish. "I'm not a writer. I think I can write short stories and poetry, but film writing, brilliant film writing, is a talent - you can't just do it like that." She clicks her fingers.
Eventually, she asked Tony Grisoni, who adapted David Peace's Red Riding trilogy for television, to write the screenplay, and he created a film that is not about murdered prostitutes, and not literally her life story, but is close enough to make her family shudder with recognition.
"There are a lot of similarities between me and Lucy, but my mum and my dad and my eight brothers and sisters can all watch the film and go, 'We know that's not our story, but we get why she's done it.' At the same time I do love them and I do respect them, and I'm not about to exploit them."
Morton was first taken into care as a baby. She never learned why as a child, and remains unsure to this day. Everybody concerned - mother, father, social services - has a different version of the truth. Family life was certainly not helped when her father got the 15-year-old babysitter pregnant (he went on to marry her) and her mother moved in with an alcoholic. There were times when Morton returned to live with her father until she was eight. Then she was made a ward of court, which meant she could never return home - again, something she didn't know at the time. She describes her father as a "brilliant man", a huge influence on her life, so desperate to be a good dad. She has not always felt like this about him.
Did he hit her? "Yes. Yep." Badly? "Yep." The most horrific thing about the violence in The Unloved is its inevitability. However senseless, and however much Lucy's father tries to stop himself, we know just what's coming next. He even provides a tortured running commentary as his willpower fails him. I ask Morton if her father hit her in a similar way. "I think anybody who has been abused as a kid - and I was abused as a kid, by various people - will say it's irrational because violence is irrational. It is a criminal offence for you to hit me or me to hit you, but it is not a criminal offence for a parent to hit a child. What gives one person the right to be violent with another person, especially a person who cannot understand? Baby P... My mind boggles at the amount of violence inflicted upon children in today's society."
When I first meet Morton I don't recognise her. As an actress, she has a remarkable gift for playing real people rather than "characters"; in films such as Control and Under The Skin, she is unadorned, simply dressed, raw to the core. Today, she looks as if she's stepped straight off the set of a Victorian melodrama. Her hair is wrapped, dense and high, in a bird's nest, her dress low cut, full-length and floral, her fingers clamped in vintage rings. But this is not Morton in character, this is Morton as herself. "I look like a cross between an Enid Blyton character and a prostitute." She laughs, quietly at first, then louder and louder, like a batty Julie Walters creation of 20 years ago, She's always been locked into the past, she says.
In The Unloved, Lucy hardly says a word. Rather than living her life, she seems to be observing it. Morton says this is common in abused children. "You read a lot about this in psychology, how children almost astral project. They throw themselves out of their body and it's almost bordering on the autistic spectrum. They are spectators of their reality. They are quite numb." That's why the sound is so heightened, she says, because Lucy is living in the echo-chamber of her own head.
From the age of eight, Morton moved between care homes and foster parents. Any number of them - she can't remember how many. She says The Unloved is a censored version of what she experienced. What did she dilute? "Violence, sexual abuse, torture..." If she had included everything, nobody would have believed her, and anyway, it was always intended to be a film that children could watch. "I'm not going to make a children's film and turn it into a horror film. I wanted to make a film that someone from the age of 13 could watch and get, and it would change them." It was also important to Morton that the film would be shown on television before its cinema release. After all, she says, that's where people such as her experienced film for the first time, watching the likes of Kes on the telly at school.
It's funny, she says, when she was really little she was a right scrapper, frightened of nothing or nobody. "If somebody bullied someone else, I'd go and knock them out." Then she withdrew into herself. And eventually she found a new kind of strength. "One day I just thought, what can you do to me, really?" She sings me a line from the Robin Hood song: "He's a fighter not looking for a fight" and says that's her. "My answer in my late adolescence was not fight back. It was to say, you can do anything to me but you won't really upset me. That's why Psalm 27 is at the beginning of the film: 'The Lord is my light... Whom shall I fear?' Because you can do anything to me, physically, but you can't get in here," she says pointing to her heart, or maybe her soul. The Catholicism she grew up with - iconic imagery, knees sore from praying, guilt - never really leaves you, she says, no matter how much you might think you have left it.
Morton went to a good comprehensive school, neighbouring a wealthy area. But she always felt an outsider. "The houses on that road are million-pound ones, yet I was living in a children's home two buses away, where I was up most nights because of riots or sharing a room with a prostitute. You can't get your homework done and you fall behind." At 13, she left school for the last time, spending most of her early teens raving, taking ecstasy and hallucinogenics with older children and young adults, lawless and lost. Sometimes she returned, or was returned, to the homes or foster parents. Between 13 and 14, she was homeless for almost a year, sleeping at friends' houses or in bus shelters.
How close does she think she was to screwing up her life irredeemably? "Massively. Completely. Massively." Does she think she could have ended up selling sex, like the friends who were murdered? "No, not that kind of darkness. No, for me it was drugs."
Although Morton turned her back on school, she was jealous of those who had a regular education. "I had a massive chip on my shoulder, like a big bag of McCains. I walked past the girls' high school in Nottingham, a private school, and I'd see them bunking off, and I'd think, you twats, your parents are spending a fortune on your education. I was very bitter, I suppose. My appetite for knowledge and literature and music was massive. The reason I didn't go to school was because, at that point, I'd already - excuse my language - fucked it because I'd run away so much when I was younger." So she determined to educate herself. "Someone said to me if you read the Guardian and the Times every day, you'll learn everything you need to know." Who was it? "A drug dealer of mine." She smiles.
Presumably, much of her anger was directed at her parents? No, she says instantly. "Never, never my parents. Always authority. Always the establishment. That's because I grew up in Nottinghamshire in the 80s with Margaret Thatcher destroying everything." As for her mother, she says she would make a great character in a Loach film. "She lost a lot of her rights as a woman and a mother very early on. I'm not going into it too much, it's her business." It's surprising, and touching, how protective she is of her parents. "Just because somebody doesn't bring up their children or can't look after their children doesn't make them a bad person," she says of her mother. "There are all sorts of reasons - illness. There are so many reasons you can end up in care."
In addition to raving, her other source of release through her early teens was acting. Here she could lose herself in a healthier way. At 13, she was picked to join the Central Television Workshop for young actors. Her intensity marked her out as special and a little scary - if she was asked to improvise conflict, it would often nearly end in a fight.
At 16, she moved to London and was cast in roles uncomfortably close to her own history - in Cracker she played a pregnant teenager (Morton had an abortion at 16), a car thief in Boon, a junkie, homicidal prostitute in Band Of Gold.
She has a knack of bringing a disarming, everyday quality to extreme characters. In Under The Skin, one of her first starring roles, Iris is a woman numb with grief who beds stranger after stranger as she tries to force her way back into feeling. As Myra Hindley in Longford she flits from vulnerable tenderness to monstrous manipulation, toying with us so subtly that we're never sure where we stand. Occasionally, her characters are so quiet they almost disappear - in Control, it is such a shock when downtrodden Debbie Curtis finally raises her voices and stands up for herself, you almost jump out of your seat.
Good actors are often said to unpeel layers of skin in front of us. At her best, Morton doesn't seem to have skin in the first place. Sometimes, I say, acting almost appears to be an out-of-body experience for her. She nods enthusiastically: "When I do takes at work, if I'm not completely somewhere else I always have to go again. It's almost like madness." And she says that she's unlikely to direct another film, however well The Unloved does. "I'm an actor. That's what I'm gifted at. It's what makes me breathe. People say when they self-harm it's to breathe, to live. My self-harm, if you like, is acting, because I feel alive when I do it. I cannot live without it."
In the past she has said things got so bad that in her mid-teens she contemplated killing herself. I ask why, and she goes quiet. Look, she says, you're young and homeless, you're involved in drugs and crime, you think you're in control and you're anything but. "You're still a kid and you think you're a grown-up. I did awful things at times, and I did those awful things through being under the influence of drugs or not being kind to myself and not loving myself and not knowing how to be kind." She pauses.
"Between the ages of 14 and 16 I was in a very dark place and then came out of it."
"Were you stealing a lot?"
"Um, yeah, but no," she says. "I had to steal my food. I stole from shops to eat, and that's different from stealing for the sake of it, for fun or a dare."
How did that darkness express itself? Through depression? "No. I got into trouble with the police quite seriously as a kid. And I thought, this could affect the rest of my life."
Did you get convicted? "As a mother I have to be very careful what I say. Everything I say to you now I have to feel I could have that conversation with my children because it's going to be in print." Did the conviction result in a sentence? "Yes." For a week or a month or a year? "It was an 18-week sentence at an attendance centre."
And was that what changed you? "Yes, revolutionised me. I felt humbled, I felt remorse, I felt embarrassed. I felt better than the way I was treating myself. I was a twat. I was a little twat. I can be kinder to myself and say there were reasons why, but at the end of the day you can't justify certain things, you have to grow up and get on with it."
We talk a week later. She's been thinking a lot about the conviction and says that if ever there were a time to talk about it, it's now, with the film. "I was physically abused, bullied by someone for a long time, and I retaliated. We were kids, products of a crap environment. The only person I hurt in the end was myself."
She explains what happened. "There was a riot in the home, a fire, it was like a mini Strangeways. The police were already there, and I'd been tripping and was still a bit out of it. I threatened to kill the girl and picked up a knife. I didn't touch her - wouldn't have touched her - but the police restrained me and then arrested me.
"I was locked in a cell for three days. It was terrible. I just sat there thinking, I don't want this life - I'm not a petty criminal, I'm not a thug. But that's how they were treating me, understandably. I was so ashamed of myself."
The case went to the local youth court, then the crown court. She was charged with attempted murder, but was eventually convicted of the lesser charge of threats to kill. Morton says there was a terrible sense of history repeating itself; her stepfather, whom she calls inspirational, was in prison at the time - for attempted murder. "Some of the homes I was in were fine, but this place was awful. It's being closed down now. I go into homes today and see kids like I was, like this girl was, and I just want to take them home and look after them."
Even today, the conviction has an impact on her life. Whenever she wants to travel to America to work, she has to fight for a visa. "When I did Sweet And Lowdown, I had to sit down with Woody Allen and explain everything. Awful. It happens all the time."
On the one hand her childhood is in the past - but it's a past she's still coming to terms with. "Look," she says, "things have gone swimmingly since I was 16." It's largely true. She has worked consistently, she has made blockbusters in Hollywood (Minority Report with Tom Cruise), she's been nominated for two Oscars (Allen's Sweet And Lowdown and Jim Sheridan's In America), and starred in more than her fair share of British arthouse classics (Morvern Callar, Control, Under The Skin). She has made money along the way, campaigned against the closure of state-funded children's homes (however corrupted they are, in some cases they remain the safest option) and been embraced as one of the great actors of her generation.
"And two children," she interjects. "I think the best thing in my life is my ability to be in a stable relationship. For anybody who has been in care or moved around a lot, it's very tough to form strong, lasting relationships. And that's what I'm proudest of." She has been with her fiancé, Harry Holm, son of actor Ian Holm, for four years. Their baby, Edie, is 15 months old. "He's my first serious partner. Anybody who has been in care says if you achieve that, that is success. You're happy." They live in London with the two children and five cats. She used to have 11 - most of them strays. "People bring them to me. I think of myself as a cat foster mum."
Yet, in true Morton fashion, not everything has been easy. She split up with the father of her older daughter, Esme, now nine, before the birth. She has a history of troubled relationships. Professionally, she got a reputation for being difficult. (Fair enough, she says, she was difficult in the past, telling crew members to shut it if they were chatting away when she was giving her all - she works hard and expects others to do so, too.) And two years ago she suffered a freak stroke after her ceiling collapsed on her. She says it was terrifying, especially as a young mother. "A piece of 17th-century plaster fell on my head. I went to the hospital and everything was OK, and then it wasn't. I spent a long time in rehab learning how to walk and getting better, and then went straight off to make Synecdoche, New York." Is she OK now? "I still have a slight disfluency, sentences are spaced differently, but I was given a clean bill of health."
She knows how lucky she's been - in every way. But she's not one for complacency. There's always something nudging her, whispering in her ear, asking if she's making the best use of her life. "There are days when I thank my lucky stars that I'm OK and that I'm sane, and wonder how I ended up doing this job. Then there are days when I think, is this the right job for me still? Shouldn't I be doing something in social care or politics?"
Does she think she will some day? "Yeah, definitely. I think I will combine the two and find my way, doing something with charity work, and helping the government with reform of the way children are treated, educating young people. Some people have had a tough time, they've been in care or whatever, and they leave it behind them. Off they go and ride off into the sunset with a nice house and, y'know..." She pauses. "I'm always going back. It's still so much part of me."