William Burroughs led the low life characterised by drugs, crime and random sex and wrote the books 'Junkie', 'The Naked Lunch' and 'The Ticket That Exploded' which captured the renegade spirit of the Beat Generation. Born in 1914, after an anonymous childhood and education at Harvard University, he avoided wartime service, and moved to Chicago where he imbibed the influences which were to make him a legend, ironically indifferent to his reputation. No one influenced him more, however, than the woman he married. And killed.

Joan Vollmer was a student of journalism at Columbia University, who was bringing up a daughter from a recently defunct marriage when she moved into an apartment on 115th Street with Edie Parker and Kerouac. Her room-mates enlisted Ginsberg's help to bring her and Burroughs together. "Jack and I decided that Joan and Bill would make a great couple," recalls Ginsberg. "They were a match for each other, fit for each other, equally tuned and equally witty and funny and intelligent and equally well-read, equally refined." They were also equally interested in drug-taking, with Joan consuming Benzedrine at an impressive rate - so much so that she was prone to fits of psychosis, aural hallucinations and paranoia. Yet she appeared composed around her new lover, who shared her interest in Mayan magic and appreciated her acerbic sense of humour. Joan was aware of Burroughs's homosexuality but saw no conflict of interest, jokingly complimenting him that he made love better than any pimp she had ever known.

In the summer of 1945, Burroughs moved into Joan's apartment and, when Edie Parker left after she and Kerouac split up, Ginsberg settled there too. It is from this point that the nucleus of a Beat family began to take shape: Ginsberg, Kerouac, Burroughs and Joan all living under the same roof, an alternative household sharing drugs, books, sex and ideas. The group would often play out various psycho-dramas, role-playing routines in which each member would assume the guise of some unlikely character and interact with other characters in an extemporaneous routine. A 19th- century lesbian governess, a Hungarian psychoanalyst, a cracker-barrel Southern sheriff - all regular personae for their own entertainment.

Not that this scene was necessarily all fun and games. Joan was relying heavily on nasal inhalers to get her Benzedrine rush and was becoming more and more prone to paranoia. She began imagining that some of her neighbours were accusing her of running a brothel, whilst others were trying to murder each other. Hysteria and hallucinations became as commonplace as discussions about poetry and with Kerouac hitting the bottle and Burroughs on the needle, the whole place was deteriorating into dysfunction - and dependence. When the place was eventually busted for narcotics, in April 1946, there was a sense of tragic inevitability about the raid. Burroughs, who had been forging prescriptions, was given a four-month suspended sentence and released into his father's custody.

In Burroughs's absence, Joan's condition became acute, her speed-use culminating in her having to be admitted to Bellevue psychiatric hospital for a 10-day detox. Given that they were about to be evicted anyway for non-payment of rent, Ginsberg abandoned the apartment and wrote to Burroughs informing him of Joan's illness. Burroughs returned to New York and rented a hotel room for himself and Joan. New York, it seemed, was devouring them and so, while Joan rested in their hotel in Times Square, Burroughs began devising ways for them to get out of the city unscathed.

Joan had become pregnant in the course of her recovery, and a ranch in Texas held out the glimmer of a fresh start. After the urban burn-out of New York, Burroughs and Joan entertained a fantasy of rustic retreat. In January 1947, they moved to New Waverley, near Houston.

But their image of a rural idyll was stillborn from the start. The couple invited Huncke to join them, but, rather than being the dutiful farmhand, he was soon making trips to Houston to buy inhalers for Joan, morphine for Burroughs and marijuana seeds as a crop. The Waltons they weren't, and drug use became the most convenient way of killing time.

In fact, their time in Texas was tedious and bleak. On 21 July, Joan went into labour and gave birth to William Burroughs III, a child who was born addicted to speed and spent his first few weeks in the world going through an involuntary detox. Joan had to bottle-feed her baby as her own breast milk was laced with amphetamines.

Ginsberg brought his new love, Neal Cassady, down for a visit, to find a household that was as singularly strung-out as the one he had shared with them in New York. Even worse, his attempt to seduce Cassady failed.

Neither was the venture profitable. When Cassady, Huncke and Burroughs drove the 2,000 miles back to New York with their pot crop, they found a barren market. Eventually they cut their losses and sold the whole stash for $100 wholesale.

If further proof were needed that it was time to leave Texas, it came when Burroughs was arrested for having drunken sex with Joan in his car. A fine of $173, the loss of his licence and the attention of the police were enough to convince him. Joan and Burroughs sold the farm and tried another new start, this time at 509 Wagner Street in Algiers, New Orleans.

If Texas had been perceived as a haven from drugs, New Orleans was sought out as their heaven. The Big Easy lived up to its name, abundant in junk connections and dope peddlers. The appeal of New Orleans was also its downfall, as Joan's speed habit and Burrough's own junk sickness gradually brought them to a state of virtual paralysis.

Eventually, their house was raided and the police uncovered stashes of heroin, marijuana and a collection of firearms. "If convicted," Burroughs wrote to Ginsberg, "I am subject to 2-5 years in Angola [one of the meanest state penitentiaries in the country], which is definitely not a Country Club." Fortunately his lawyer proved that the search had been illegal, but he also advised Burroughs that it would be politic to leave the country. Late in 1949, Burroughs took Joan and the children and moved to Mexico City.

The period stretching from New York to New Orleans provided the raw material for his first novel, Junkie, although it was not until his arrival in Mexico that he began to conceive of writing it. On 1 May 1950, he wrote to Ginsberg: "I have been working on a novel about junk. It is about finished now. May realize a few $, but I doubt if anyone will publish it, owing to the criticism of the Narc [-otics] dept. it contains." By the end of that year, as he and his family were settling into their new home on 37 Cerranda de Medellin, the first draft of the book was complete.

As the manuscript gathered dust, Burroughs continued his on-and-off courtship of junk, and Joan's taste for inhalers increased. Booze had also become a key factor in their lifestyle. Whenever Burroughs kicked heroin, he would use alcohol as a substitute, drinking straight tequila for eight- hour stretches. At one point, he developed uraemia and was advised by his doctor to return to morphine. For Joan, drink and speed perversely complemented each other - the booze took the edge off her speed-induced paranoia, and the speed allowed her to consume more booze.

It was against this background of self-destructive co-dependence that the event which would change Burrough's life took place. On 6 September 1951, he and Joan decided to sell one of his handguns via their friend John Healy. They had been drinking all afternoon before arriving at Healy's apartment at 6pm. When the buyer failed to show up, the couple continued to hit the bottle. "I began throwing down one drink after the other," said Burroughs. "I was very drunk. I suddenly said, 'It's time for our William Tell act. Put a glass on your head'." With the carefree abandon of a hardened drinker, Joan laughingly agreed, although it was the first time they had played the game. She balanced a six-ounce water glass on her head, and Burroughs fired a bullet through her temple. The pronouncement of death at the Red Cross Hospital was a formality.

Much speculation has been given to the killing. Was Joan suicidal, or acting out the nihilistic bravado of an alcoholic? Was Burroughs homicidal and using the game as a cover for murder? There was certainly nothing premeditated about the event, and the most plausible explanation is simply that Joan's death was an accident brought about by drunken abandon.

The most tragic irony of the episode is that Joan's death forced Burroughs into taking himself seriously as a writer. As he was to comment later: "I am forced to the appalling conclusion that I would never have become a writer but for Joan's death, and to a realisation of the extent to which this event has motivated and formulated my writing. I live with the constant threat of possession, and a constant need to escape from possession, from control. So the death of Joan brought me in contact with the invader, the Ugly Spirit and manoeuvred me into a lifelong struggle, in which I have had no choice except to write my way out."