Murder, violence and the rest of the darker deeds of the human race have always been meat and drink to the occupants of the now deserted newspaper building in Withy Grove, Manchester. Once they made the headlines of the papers that passers-by could see screaming off the presses, bundled into waiting vans in the cavernous, ground floor loading bay and rushed out into the night. More recently, they have reared their ugly heads when its empty rooms with their peeling paintwork have been used as location sets for such rugged television dramas such as Prime Suspect and Between The Lines. And today all kinds of hell are being let loose again. This time the abandoned offices transform themselves into Anson Road nick, the less than salubrious headquarters of Fitz, Panhandle, DCI Wise and the rest of the now familiar Cracker team of crimebeaters. At the end of a bare corridor, deep inside the multi storey maze, tension hangs in the stale air. Detective Sergeant Jane Penhaligon (Geraldine Somerville) and Detective Chief Inspector Wise (Ricky Tomlinson) round the bend and walk towards the camera. Wise duck into an office to leave the unsuspecting Penhaligon to stroll on alone. And then it happens - one of those short arm verbal jabs that seem to come from nowhere to leave both recipient and audience gasping for breath. "Oh by the way,"begins Wise, innocuously enough as he reemerges with an after thought directed at Penhaligon's disappearing back, "Jimmy Beck's coming back in the morning". There are no histrionics - just a falter in the stride, a glazing of the eyes and a hand which comes involuntarily to cover a tightening mouth. After all, how are you expected to react to the news that the man who you believe to be your rapist is coming back to work alongside you? 

A few minutes later I put that question to Geraldine Somerville as she stretched out in her caravan, still visibly shaken by the scene she has just played. "How do you mean 'believe?'"she said with sudden vehemence, "He damn well did rape me!". And in that brief unguarded moment came the dawning of an explanation why Cracker - in just two series - has taken a stranglehold on its devoted television fan club. Powered by Jimmy McGovern's brutally minimalist dialogue, even the actors can become so immersed in their characters as to forget that they are merely the peddlers of make believe. And if Geraldine Somerville was feeling a rebirth of outrage, self-disgust and burning anger with which she finished the last series (remember the pistol in Beck's mouth, the last enigmatic phonecall to Fitz?) then what chance have the rest of us to distinguish between fact and fiction. "Oh yes, it was very hard to imagine how Jane would react,"she said, becoming an actress again with a hint of bashful apology for untypical outburst, "All you can do is feel your way into it. Its like being happy and smiling one moment and then seeing your dogs dead. How's it going to affect you? Violently, of course, but in what form? I had many sleepless nights thinking about it, I can tell you. But from research I soon discovered that it happens more often than you think. A lot of victims know their assailants. They know they are out there, living a few doors away or working at a desk nearby. It's chilling - but it goes on all the time".

If Geraldine Somerville was feeling the strain of living under the skin of a policewoman undergoing the kind of mental torture that is Cracker's and McGovern's trademark - "I like her all right, but I wouldn't want to be like her, she's so awe inspiringly courageous" - it might come as some solace to learn that Lorcan Cranitch, that irrepressibly cheerful Irish actor saddled with the task of bringing to life the detective who defiled her, wasn't finding his job all that comfortable either. "I'm not sure that Jimmy Beck is a man I would like to spend much time with,"he said as he relaxed between scenes in a neighbouring caravan, "I can understand him because I've been living with him for so long, but he's such a dark character that it can get pretty scary. You've got to go places in yourself that you don't want to go to. A few years ago there was a story back home [in the Republic of Ireland] about a 14 year old girl who was raped by a relative. It went on to divide the whole country on abortion. I remember at the time feeling horrified by what had happened. I am a man as well, and I certainly have the physical aptitude to do such a thing - I just pray I'll never have the mental aptitude." 

Despite the sinister, often macabre, storylines, the brutal authenticity of the action and the shafts of humour, the sheer unexpectedness of which can sometimes appear as shocking as the abounding ungodliness their punctuate, McGovern insists that most of his cast of characters were total strangers to him when he embarked on writing the series. "I knew all about Fitz - I knew him inside out - but I had no idea who the coppers were"he says, "You cast the actors and the actors bring their own personalities to bear. You watch the rushes and see the sort of people they are. They develop their own histories, their own backgrounds. If something happens to them in one episode, then you jot it down in your mind for another occasion. I've got a tiger by the tail and its thrilling". With only one regret. The did-he-or-didn't-he assault which led up to that violent encounter between Penhaligon and Beck was, of course, a sidebar to the main plot - the pursuit and breaking down by Fitz and co of a black serial rapist whose victims are all white. 

As soon as the theme became known, Granada's studios were beset by protestors, accusing the programme makers - and particularly its author - of stereotyped fascism. But McGovern, surprisingly gentle and soft spoken for a writer whose pen seems so often to be filled with blood, remains unrepentant. "We tackle big themes, themes which people care about,"he says, "The only thing that saddened me was that we were attacked before anyone knew the story. If they had waited until they had seen it they would have known that there was the right to reply programmed into it. We don't aim to provoke or exploit - we explore."But perhaps such public remonstration is merely further proof that Cracker had finally ceased to be Monday night escapism and has somehow become a part of the world outside. It has become something to be argued over, analyzed and alarmed by - the difference between an ordinary sleepless night of a right rollocking nightmare.