He was the Dr Jekyll of Hyde, a family doctor whose seemingly caring manner hid a terrible secret. Nick Morrison looks at the life and death of Britain's worst serial killer.

IT was the state-of-the-art practice he had always dreamed of, equipped with the latest medical and computer equipment - a mini-hospital to serve his 3,000 patients. So pleased was he with his baby that he was planning to expand, keeping a donations box in the surgery so his patients could help fund his scheme.

But this dream never came to pass. Harold Shipman never did get to buy the shop next door. For the last five-and-a-half years, the metal shutters have been down at 21 Market Street in Hyde, on the outskirts of Manchester. Yesterday, just hours after Shipman's death by his own hand in Wakefield Prison, the word "justice" had been scrawled 12 times across those shutters.

Shipman may be dead, but this is a justice which means the relatives of those he killed - some 215 according to the official inquiry, with another 45 likely and 38 more where it was not possible to form a view - will never know why. It is a justice where those relatives have never heard a word of explanation, still less of remorse.

For while Shipman's death has brought an end to one of the blackest chapters in British criminal history, it has ensured that the question of what drove an apparently devoted family man, a caring doctor who was well-loved by his patients in return, to carry out such unspeakable horrors, will forever remain unanswered.

Harold Frederick Shipman, known as Fred, was born on a council estate in Nottingham on January 14, 1946, the middle child of Vera and Fred, a lorry driver. Neighbours recalled a quiet, close family, with little to distinguish Fred from the other children in the street, apart from the fact he was clever. He won a scholarship to grammar school, passing seven O-levels and three A-levels. While he was taking his A-levels, Vera died of cancer at the age of 42.

Shipman won a place to study medicine at Leeds University, where his fellow students remembered him as an unremarkable man. But it was during this time that he met and married Primrose Oxtoby, a window-dresser and daughter of a council worker from Wetherby. Shipman was just 20 and Primrose 17 and pregnant when they married. Their first child, Sarah Rosemary, was born the following year, and son Frederick Christopher four years later, in 1968.

After working in a hospital, Shipman got a job at a GP practice in Todmorden, West Yorkshire, where both colleagues and patients were impressed by his dedication. The young family settled into life in a Pennine valley, Fred helping restore the Rochdale canal and Primrose joining the local choral society.

But just over a year later it all went wrong, when Shipman was charged with drug offences. He had become addicted to pethedine, normally used to relieve labour pains, and had been injecting himself to stave off depression. To cover up the large amounts of the drug he had been using, he had begun falsifying prescriptions, the same method he was later to put to chilling use.

He resigned from the practice and was fined £600, but escaped being struck off and instead was treated at a psychiatric and drug abuse centre in York. He found work as a medical officer in south-west Durham, but this lasted only three weeks before he joined the Donneybrook House medical practice in Hyde in 1977.

The family moved into a semi-detached house which was to remain their home until Shipman's arrest, and two years later their third child, David Julian, was born, followed by Samuel James in 1982.

Shipman became a parent governor at one of the children's schools and acted as a volunteer for the St John Ambulance. Holidays were often spent camping in France, and the family lived a quiet life.

But it was a life dominated by Shipman. Primrose was said to be completely in his thrall, the submissive partner to her domineering husband. Family meals could not start until Shipman returned home, and their relationship has been likened to that between a puppet and its master.

Shipman was popular with his patients, but colleagues spoke of another side to him, one which would brook no argument and he was volatile when crossed, capable of temper tantrums with his subordinates, although never with the other doctors. By the time he left, he was communicating with the practice manager only by letter, even though he walked past her every day.

In 1992, he left to set up a one-man practice at Donneybrook, five months later moving to Market Street. With Primrose on reception, he installed the latest computer system, a system he would later use to forge the medical histories of his victims. Three years later, he carried out the first of the killings for which he was convicted, when he injected 81-year-old Marie West with a fatal dose of morphine as she sat in her front room.

But his killing spree had actually started 20 years earlier, while he was working in Todmorden. There, he murdered Eva Lyons, in March 1975. Another 71 patients were killed while he worked at the Donneybrook House practice, with the remaining 143 of his confirmed victims dying while he ran his one-man practice.

He came close to detection in 1994, when he gave Renate Overton an overdose of diamorphine when she had an asthma attack. Mrs Overton fell into a coma and died 14 months later, but no inquest was held and a post-mortem failed to pick up the overdose. Shipman went on to kill around 100 more patients.

Another escape for Shipman came in March 1998, when another GP told the coroner of her suspicions about the high number of his patients dying at home. A police investigation was carried out, but failed to include post-mortems on another two patients, which would probably have revealed traces of morphine, and did not check Shipman's previous criminal record. Another three women were to die at Shipman's hands.

In September 1998, he made the mistake which was to bring his murderous activities to an end. Kathleen Grundy, 81, died hours after Shipman visited her home to take a blood sample. The same day, a firm of solicitors received a will purporting to be that of Mrs Grundy, leaving all her estate to her doctor, Dr HF Shipman, of Market Street, Hyde.

Mrs Grundy's daughter, a solicitor, became suspicious, and when police examined the will they found it had been produced on Shipman's typewriter. The forgery was said by police to be so cack-handed that it was inevitable Shipman would be caught, and there has been speculation that it was a deliberate attempt to bring his killing spree to an end. Shipman was arrested on suspicion of forging Mrs Grundy's will, but when her body was exhumed, traces of morphine were discovered. Shipman was then arrested on suspicion of murder, beginning the grim discovery of the largest serial killing in British criminal history.

At his trial, which ended in January 2000, Shipman was convicted of 15 counts of murder, but the subsequent public inquiry found another 200 deaths for which he could be held responsible. But in police interviews, where he was described as arrogant and contemptuous, throughout the trial and afterwards in prison, Shipman refused to acknowledge his part in the deaths. His defiance has meant no convincing explanation for his actions has ever been forthcoming.

Conjecture has included the theory that Shipman enjoyed playing God - being able to take life away as well as prolong it, a theory given credence by his arrogance and controlling tendency. Some have suggested he got a sexual kick out of inducing death, perhaps nurtured by the shock of losing his mother.

For her part, Primrose, who now lives in a house next to the A1 near Wetherby, has loyally stood by her husband, refusing to believe in his guilt and sitting through every one of the 57 days of his trial. Some ask how she could not have known something was going on, but she had remained defiantly devoted to her husband. Even though his life is now over, his influence is still there to see.