The devil's advocate

''I CUT her legs off and, I mean, that was unbearable,'' the man is saying. ''I can still hear that in my sleep. And I cut her head off and I closed her eyes first 'cos, well, you're not going to take a saw to your own daughter when she's sat there looking at you, are you? And then she fit neatly in the bin.''

Janet Leach, a Gloucester housewife who recently completed the training to sit in on such police interviews, listens with dawning horror. This is her first encounter with Fred West, who will later admit to killing at least 10 more girls after raping them in the basement of his suburban home.

The scene occurs within the first few minutes of the British telemovie Appropriate Adult and by the end of the monologue - delivered so compellingly by Dominic West that it won him the part - Janet's life as she knew it is over.

Leach is the vehicle through which the film visits the true story of Fred and Rose West, beginning when she first met Fred and ending with his suicide 10 months later. Leach (Emily Watson) was appointed West's ''appropriate adult'' - a role that involved safeguarding the rights of minors and vulnerable adults in police interviews, and he grew to depend on her, revealing information that she was bound by confidentiality not to disclose.

But he also manipulated her - and there is more than an element of Hannibal Lector and Clarice Starling in their relationship.

Indeed, it was this relationship, and the way in which it illuminated shades of human nature, that convinced the production team to make the film. Executive producer Jeff Pope, writer Neil McKay and producer Lisa Gilchrist, had completed two other award-winning films about British serial killers - This is Personal: The Hunt for the Yorkshire Ripper and See No Evil: The Moors Murders. But they initially dismissed a film on the Wests' crimes as too distasteful.

''To have done a piece about Fred and Rose and why they did what they did, quite apart from the fact that it would have been grizzly and revolting, I think it would have been quite dull,'' Pope says.

''I don't think there's anything to learn by visiting them. Much more interesting to come into the story through an Everyman - and that person was Janet.

''I'd read some material about the West murders … and it was, frankly, one of the most disturbing things I'd ever read. I was just at the point of thinking, 'No, there isn't anything in it', and there she was. She just seemed to pop out of the page.''

The next stumbling block was gaining Leach's permission, without which they were adamant the film would not be made. Letters and approaches through intermediaries went unanswered, so they eventually decided to knock on her door. It risked alienating her but Pope didn't want to give up until he was sure she didn't want to do it. She took some persuading.

''She was a profoundly, profoundly damaged person,'' Pope says. ''In fact, one of the most inspiring things was how she rebuilt her life. She'd suffered a nervous breakdown, she's suffered many strokes during the trial, she'd suffered appallingly, she'd sued Gloucester Police.

''An essentially untrained person would never be put in that position again. She was put in a room for hour after hour with one of the most notorious serial killers in Britain's history. But … underneath it all, the reason she'd carried on seeing Fred West [was] this terrible feeling of duty towards the people that Fred and Rose West had murdered.''

As to why she agreed to participate, Pope can only speculate. The case not only took a toll on her own health, but that of her family, which is explored in the film. ''I believe it's cathartic,'' Pope says. ''One of … a whole lot of factors that we needed to take into account before we embarked on the whole process [was] definitely whether Janet would get something out of this. What we didn't want to do was put the glare or spotlight back on her and ruin her life.''

Once Leach was on board there was the matter of casting. Emily Watson was quickly recruited to play the title role but casting Fred West was more arduous. Several actors who were approached recoiled from the material and The Wire's Dominic West - tall, slim, handsome - wasn't an obvious choice to play the chubby, unkempt Gloucester builder.

''But I knew that whoever ended up doing this job, it wouldn't be a maybe, it would be an emphatic 'yes','' Pope says. ''I didn't think we could approach this half-heartedly, and that was exactly what happened with Dominic. He read the soliloquy from Fred about how he'd dismembered his daughter - and we knew immediately. He got intuitively that casual air Fred had when he was talking about murdering and dismembering his victims.''

It was then up to the make-up artists to give him cracked teeth, a ruddy complexion and padding, to make him look more burly.

Not surprisingly, the film was controversial in Britain. Anne-Marie Davis, one of the Wests' surviving daughters, accused the producers of acting solely in the interests of money at the expense of the victims' families, who she said would be more distressed by the film.

Pope counters that she made the comments without seeing the film and that the Wests' other daughters, as well as many victims' families, were supportive of the project.

Some of the families saw it as an opportunity to celebrate the lives of their daughters, using new photos besides the black-and-white mug shots published in the newspapers.

In that sense, he sees the drama as more about life than death. He compares it with another of his films, Pierrepoint: The Last Hangman, a biopic of Britain's most prolific executioner, who tried and failed to separate his job from his humanity. ''It was a sad story and it was about how the human spirit can't be subverted,'' Pope says. ''I feel the same about this. Janet survived this experience and came out stronger.''

Appropriate Adult
Seven, Monday, 8.30pm

The story The devil's advocate first appeared on The Sydney Morning Herald.

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