Impact without crash-bang-wallop: No screaming tyres, no sawn-offs, barely a shot fired. Yet Between the Lines is the best police drama on TV. Sabine Durrant talks to its creator, J C Wilsher, and star, Neil Pearson

In an ordinary house in an ordinary street in north London sits a man with a suntan. A winter suntan. 'Er . . . St Lucia,' the man says, his forefinger clamped protectively against his mouth. He gives a fresh-off-the-plane holiday spiel (you know: sun, snorkelling, big portions at the hotel buffet), but with a rigidity in the shoulders and a stiffness of the facial muscles that say, 'This isn't the sort of thing I usually do.' Perhaps it isn't. But there's no getting away from it: this is the sort of thing he'll be able to do from now on.

J C (no relation to PC) Wilsher's life has been thrown into a new gear by Between the Lines, the internal investigation police drama which squealed out of its second series just before Christmas and sits purring for its third. Created and largely written by Wilsher, the show was a big critical success - winning an award, loved by reviewers, talked about in offices the day after. The ratings, though, remained bafflingly low (perhaps because it's a cop show with precious little shooting, a dismal arrest-rate and mountains of paperwork), which may be one reason why the BBC has decided to repeat the first series on Saturday nights - too convinced of its greatness to let it lie.

Whether the attention of the stray five million or so will be arrested by this tactic or not, Wilsher's in the clear. 'Lots of the people in the BBC, and I think all the major independent producers, have asked me in to talk to them,' he says. 'Which is nice.' Exciting projects, gold savings accounts, Caribbean holidays, then? Wilsher smiles sheepishly, 'Well, it cheered me up,' he says.

A lugubrious man with a sudden sawn-off shotgun laugh, Wilsher's precise directions from the Tube and the functionality of his front room (not to mention the precision of his research) make you think he might be an ex-policeman. But he's not: 'There's a photograph of me wearing a policeman's hat at the age of eight, but after that no, not at all. I wasn't physical, I wasn't that kind of person . . .' In fact, aside from a brief stint as an armoured van Securicor driver, J C Wilsher (that is John Charles Wilsher, actually Dr John Charles Wilsher) has had an academic past, researching 'Leisure' ('Yes, yes, I know' - weary look) at Lancaster University before giving it up to write.

He had written a couple of television plays and 'a lot of stuff for radio' when, in 1988, he got his first big break as one of the script-writers on The Bill. This led to him infiltrating his local Highbury beat where for most of the time, 'I couldn't shut them up. I was writing on the back of the paper, sideways . . . They were pleased that someone had come to talk to them, that they could put forward their own point of view. I'd expected the thin blue line, the wall of silence, but they weren't like that. They'd talk about racism, the Masons; they weren't sensitive at all.'

Other times, he was struck by how the cliches of real life had to be ironed out for dramatic purpose. 'I was up with an inspector at the Whittington Hospital where a girl had brought in what they suspected was a stolen baby. And the sergeant said, 'All right guv'nor, I'll give you the SP on this. We've got this girl, come in with a baby, clearly got no parenting skills. But here's a twist: the address she's given is the drum that we turned over a few months

ago looking for an armed blagger . . .'

I couldn't believe it; this stuff is just sort of coming out and I'm sitting there, thinking, 'More darling]'.'

It was during one of these forays that Wilsher first sprang the idea for Between the Lines. 'One of the CID officers I talked to - again I wouldn't have dared say, 'Have you been investigated, are you corrupt?' or whatever - but he just volunteered the information that his promotion from sergeant to inspector was delayed by two years because of an investigation, about thumping somebody or something.

'It's a subject that's always timely - particularly so at the moment because of the recent miscarriages of justice. And it struck me that, while there have been one-off films about internal investigations within the police - Serpico or Internal Affairs, say - and G F Newman's Law and Order had touched on it, the view is usually that the police are all totally corrupt - and I thought, well let's look at something with a bit more nuance.

'Basically, I suppose the dramatically interesting thing for me is what happens when you've got two guys who know the rules up against each other. One of the guys who works in CIB (Complaints Investigation Bureau, setting for Between the Lines) said to me once, 'Policemen are very good at putting up brick walls. What we have to do is take that wall down brick by brick.' Dramatically, that's a gift.'

At first, Wilsher intended to turn his idea into a straightforward series, but Tony Garnett, the executive producer, was keen that the drama should have a serial element running through it - an on-going storyline in the first series, an emotional thread in the second. It made Wilsher's task much harder. Along with the eight episodes he's written in all, he's been responsible for 'the bible' - the story arc that the other writers involved have had to swerve within. It's led to complications - seemingly unnecessary characters that set something up for a later episode, writers complaining about wasting time on 'blind' scenes - but it's also created one of the programme's strengths: the sense that its world, like the real world, is not the same week after week. Wilsher, with characteristic modesty, says he feels like he's 'created a plot mechanism rather than a bunch of characters', but Neil Pearson, the blue- eyed actor who plays Tony Clark, says, 'Wilsher's people are people not just professions'.

Everyone involved with Between the Lines insists that it's unlike other police dramas (well they would, wouldn't they, but still . . .) 'If you watch an episode of any cop drama made in the Seventies or Eighties,' Pearson says, 'you will always see screaming tyres, sawn-off shotguns; you'll always hear lots of crash-bang-wallop. But you hardly ever do in Between the Lines. So when, as in the last episode, someone does actually pull a gun and threaten to use it - Christ. You know that this guy spends his day usually snowed under by paperwork or talking to toe-raggie, low-end-of- the-market criminals and here he is up against a fully paid-up gun-toting psychopath. The unusualness of the situation works in our favour. That last episode was a great coup. I think Wilsher knew what he was doing.'

A lot of other people think so too. Wilsher, who's busy at work on Series 3 ('Same characters, different setting, that's all I'm saying'), while fending off a possible legal matter attendant on Series 2 ('No comment; if it happens it'll be all too public'), is in a position for the first time in his career to choose what he does next. He's writing a 100-minute script for the BBC, 'about an ex-policeman - naturally', and after that his options are almost limitless. 'It is gratifying,' he says, 'though nobody rings up and says they want me to do the next Jane Austen.'

Saturday, BBC 2, 10pm

(Photographs omitted)