How a humble GP perverted his medical skill to become Britain's most prolific mass killer

Shipman. Once, it was merely a name. There were seven of them in the south Manchester telephone book which covers the town of Hyde, including one, Dr HF, of The Surgery in Market Street. Today, it signifies hypodermic syringes and mass murder.

The metamorphosis began on June 1998, when the general practitioner beloved of hundreds of people in Hyde attempted to forge the £386,000 will in the name of Kathleen Grundy, a wealthy 81-year-old patient and former mayoress of Hyde.

He chose a woman whose daughter, Angela Woodruff, was a bright, sharp-witted probate lawyer. After Mrs Grundy's death, the forgery was exposed by Mrs Woodruff, police arrested Shipman and so began one of the most astonishing stories in British criminal history.

It revealed Harold Shipman ­ Fred to all who knew him, as Britain's most prolific killer. Between March 1975 and June 1998, he killed at least 179 women and 44 men, the oldest ­ 92, the youngest 41.

"You murdered each and every one of your victims by a calculated and cold-blooded perversion of your medical skills," said Shipman's trial judge, Mr Justice Forbes, jailing him on 15 murder counts on 31 January 2000.

Shipman was born in Nottingham. In 1963, while 17 and studying for A-levels, his mother Vera died of cancer,prompting speculation that it could have led to his obsession with death. Neighbours told how he watched doctors injecting her with morphine before she died.

While at Leeds University Medical School in 1965, he began going out with a farmer's daughter, Primrose Oxtoby. She became pregnant and the couple were married during Shipman's first year at university. He graduated in 1970, becoming a houseman at Pontefract General Infirmary in West Yorkshire, before joining his first practice in the Pennines. It was there he began forging prescriptions to supply himself with the painkiller pethedine, which he injected to the point where his veins collapsed. When his drug habit was discovered, he resigned. He was later fined £600 at Halifax magistrates' court on drugs and forgery charges.

But despite his case coming before the General Medical Council (GMC) he was not struck off or censured. It was only three days before his conviction that the GMC, the medical profession's disciplinary body, discovered the records of the conviction in their files.

He underwent a course of psychiatric treatment and returned to work as a medical officer in Durham before moving to the Donneybrook practice in Hyde, setting up home in nearby Mottram with Primrose and their four children. There was always an arrogant, professional superiority about Shipman.

In 1992 he left the Donneybrook practice after four months, taking 300 patients and refusing to pay his share of a tax bill. His move to 21 Market Street was the fulfilment of all he had worked for.

He established himself as a pillar of Hyde society. He chaired the local medical committee which supervised local GP practices, was a member of the local community health council and sat on the parent-teachers' association of the school in Mottram which his four children had attended. He was a generous prescriber of drugs and this made him popular.

But it later emerged that he was stockpiling diamorphine by writing false prescriptions to patients who did not need it or who had died. In total, Shipman procured 22,000mg of morphine ­ the equivalent of 1,466 fatal doses. It would emerge that he had used it to kill.

His arrogance enabled him to convince his victims' relatives that they had died naturally. A Shipman inquiry report, delivered two years ago, attempted to show how his choice of victims provided an insight into his thinking. As well as the terminally ill, he was particularly willing to kill the bereaved and seems to have killed patients who were very demanding of his time and resources, whom he regarded as nuisance.

He feared capture, the report suggested. Periodically, he stopped killing and the report suggests that near-misses may have been the cause.

There were no deaths between November 1979 and April 1981, for instance, because Shipman failed in his attempt to kill Alice Gorton. He thought she was dead and was telling her daughter that it would not be necessary to have a post-mortem examination when Mrs Gorton suddenly groaned. She was still alive.

The unexpected arrival of a district nurse appears to have had the same effect in 1989. When he began again it was the terminally ill ­ "as if he were entering the pool at the shallow end to see if he could still kill". On 7 June 1996, Leah Fogg's daughter asked Shipman to see her mother about bereavement counselling. He did, within three days, and killed Mrs Fogg.

Compiled with the help of four specialists from the Institute of Psychiatry, the inquiry report suggested Shipman chose the profession after the death of his mother. Becoming a small town GP, rather than a member of the medical elite, may also have frustrated him, the report suggests. There was certainly no financial or sexual motive for the murders. But clues to his psyche were detected in his sense of almost complete social dislocation. Active roles in the community should have yielded a large circle of friends but Shipman had none. The report also details his aggression and conceit, from the humiliation of young drugs sales reps to his behaviour at a medical lecture. A witness said: "He kept interrupting and disagreeing with the visiting lecturer in a very pompous way. His behaviour became an embarrassment."

The crudely-forged will for Kathleen Grundy may have been Shipman "raising a flag to draw attention to what he had been doing," Dame Janet's report concluded. "I think it likely that the conflict between what drove him to kill and his fear of detection... must have driven him to the edge of breakdown," she said.