Renw won the film role of Beth Heke in Once Were Warriors over 49 other hopefuls. It was a role she felt more than ready for.

'Beth was always going to be a difficult part and I knew Rena had the depth of emotion that it required,' says Riwia Brown, who was the scriptwriter and director's assistant.

The director, Lee Tamahori, endorses the view. 'This is Beth's film,' he says, 'and I knew that Rena had the power in her acting to carry it off. Her scenes arejust so extraordinary. She's not from the 'pretend' school of acting and sometimes she hovered in a knife-edge between reality and illusion. By the end of the picture you're absolutely with her.'

Beth is the wife of Jake Heke (played by Temuera Morrison), a man who speaks most eloquently with his fists. Married 18 years, they have five children and live a depressed urban life in Pine Block, a treeless Maori ghetto where the pain of unemplyment and hopelessness is regularly drowned in an endless cycle of booze and violence.

The tragedy of a daughter's suicide leaves Beth with a tough choice - stay with the man she loves, or find the strenght to get out. Not a pretty story.

Riwia Brown has centred the film around Beth and lopped off the last third of the novel to produce a film which, according to Rena, will leave audiences 'shocked, stunned, and sad'.

We talk on a brilliant late summer's morning in a place about as far removed from the bitumen-cracked footpaths of Pine Block as it is possible to be - Muriwai Beach on Auckland's west coast.

Here Rena has sunk her earnings from Warriors and the Kevin Costner film Rapa Nui, in which she had a small role, into a modest cliff-top home. It's a place to chill out in, to write in, and to provide her with a closer base to go north to her Ngati Hine whanau. It's the closest she's been since she left hometown Moerewa for Auckland in her teens, then London and later Wellington where she spent the past nine years acting, writing and directing for theatre and film.

As lazy as the day, our conversation ranges from Beth to Rena, meanders over human relationships and behaviour and then back to the Formal Interview Questions. Spiked with the odd gale of laughter and second mugs of coffee.

'I certainly don't come from a silver lining background. Moerewa was a freezing works town, notoriously Maori. We had a very large family. Freezing worker dad, Pakeha mum, Maori matriarch grandmother. Nine children. I was right in the middle. Born one after another, boom, boom, boom - they (the parents) were Catholics.

'We were a working class family and violence and booze were very much part of our lives. It was the norm for many families back then. Yet the stauchness too. Dad was brought up to carry the Ngati Hine mantle - straight from Kawiti ...

'We lived in the country, we had rivers, the creek, the sea, the mountains to play in. Our childhoods were so incredibly creative and adventurous. I look at the kids who do nothing but sit in front of screens and I feel sad because they're missing out on so much. We had a huge extended family. Every Christmas there'd be 60 or 70 of us up at Nanny's.'

Until the age of nine, Rena was convinced she was destined to become a nun. The perfect little Catholic girl. By her teens, the angel fled.

'I could have been a Beth - I know lots of Beths. I could've quite easily been a Beth if my first love hadn't messed around on me, because when I was 16 I would have been happy to live in Moerewa for the rest of my life and have lots of babies.'

Instead, the pain of breaking up with her boyfriend inspired her to achieve.

'The girl I'd been left for School C and UE and she was seen as clever. I went back to school and I really applied myself and I got School C and UE. I've seen in a lot of women's lives what pain can do - it can either drive you or it can defeat you.'

'It certainly drove me and I achieved those things and went on to do nursing (being in Auckland at 18, too frightened to walk over Grafton Bridge, the only brown face in a sea of 66 strange ones) before I went to London.'

It was in London that Rena confronted the demons of her generation - 'the generation that have ended up in prisons'. She found herself with a heroin habit and an eight-month stretch in Holloway prison.

Willpower ('incredible willpower') and therapy helped break the habit and on her release she got more breaks in theatre, one with an autobiographical play Te Awa I Tahutu, which was well receive in prison as well as by other audiences.

Since then she has worked hard at drama - writing, directing and acting. It's a love she traces back to her kapa haka days at primary school though she's glad now that she didn't go into acting straight from school.

'I think I would have done the Marilyn Monroe trip - I may have been very successful but I would have been empty and had all that mamae inside ... and it catches up with you, it really does. I had a lot to come to terms with in prison and a lot to sort out.'

One thing Rena seems to have sorted out is that acting requires discipline and hard work. That's why she felt ready to tackle Beth. During the film shoot, she had to go through emotionally in six weeks what Beth does in 18 years.

'One day I'm doing a death scene, the next day I'm doing the beating up, next day the tangi scene. She was heavy to carry, Beth. How I got through it was I basically worked morning, noon and night. So it was just work, sleep, work.'

Rena stresses the importance of preparation for the role. 'You've got to find the character. You've got to find where the lines are coming from otherwise they're just lines. I tend to work on the soul, the spirit of the person first and then I always create the first five years of their life.

'You have to be rooted in that character's world. Some of these things you may never have to use in the script. A lot of actors don't do that sort of work. I do it for my own satisfaction, my security.

'Then when you come to film a scene you've got to be able to let go, to trust the camera and yourself and go with the moment, because that's what the camera loves - that spontaneity.'

She feels passionate about playing Beth, whom she sees as a voice for an earlier generation of women trapped by domestic violence. With women's refuges and more open acknowledgment of such voilence these days, she feels there is no reason for women to stay in violent partnerships.

'But then I can't really speak because I don't have children. Some people say they stay for their children, but ultimately I don't know if a bad relationship is better for children anyway ...'

What Rena doesn't agree with (although she admires his fiction) is Alan Duff's idea that Maori can somehow magically heal the effects of generations of oppression.

'No-one wakes up and thinks, "Oh, I'm going to be a wife basher". People are conditioned by circumstances. But that's also not to condone what they do.

'Ultimately what the film is about is that Beth makes a choice. Hopefully there will be men who see the film, see Jake and recognize themselves and think, "God, is this what I look like when I do that?" For me, if it saves one person's life, then we've done our job.

And a fine job too, it seems. Rena is convinced that the film will put Maori people on the international map - 'not as drunkards or abusers, but as professional actors, writers and directors'. She urges Maori who didn't like the novel to go and see the film. Lee Tamahori describes it as having more 'heart' than the novel.

Rena would love to do more films, but no more strong Maori women for a while. 'I've got to start playing characters who are far removed from that, to stretch myself as an actor. I don't want to get typecast and I certainly don't want to keep playing victims.'

Script, anyone? Chances are, perched high on her clifftop, this 'warrior woman' may just begin writing herself.