Dr Harold "Fred" Shipman presented two faces to the world. The one seen by his loyal patients was that of the caring family doctor. But colleagues and professional contacts noted him for his overbearing arrogance.
He antagonised fellow doctors at the Donneybrook practice which he joined when he first moved to Hyde, in Tameside, Greater Manchester, in 1977.
He had left a previous post in Todmorden, West Yorkshire, under a cloud following a conviction for the misuse of drugs, then had a job in Durham.
Colleagues at Donneybrook declared he was difficult to work with, and that he felt he was above criticism.
When he left to set up practice on his own in January 1992 he alienated them further by refusing to pay an outstanding tax bill.
Yet to his patients, Shipman was the GP they felt they could trust. He was apparently dedicated to his work and had few interests outside his family life.
There was nothing in his background to explain why the genial family doctor should have become one of Britain's biggest serial killers.
Shipman was born in Nottingham and grew up on a council estate. He won a scholarship to grammar school. In 1964, the year before Shipman left to study at Leeds University Medical School, his mother died of cancer.
It was while studying at Leeds that Shipman met his future wife, Primrose. They have four children.
His first job was as a surgical house officer at Pontefract General Infirmary. A year later he moved to medicine before becoming a fully registered doctor in August 1971.
He completed diplomas in children's health and obstetrics and gynaecology before taking up the post of assistant principal GP at the Todmorden Group Practice in Yorkshire.
It was while working in Yorkshire that the first signs of instability showed. Shipman began falsifying more than 70 prescriptions to feed his own drugs habit.
He was injecting himself with pethidine, which is normally used to relieve women's labour pains, to combat depression.
The drug-taking led to Halifax magistrates fining him £600, and to his taking a two-year break from medicine, during which he underwent rehabilitation under the supervision of a psychiatrist.
Staff in the Donneybrook practice came to regard Shipman as a "Jekyll and Hyde" character. Outwardly, he was kind to patients, but he would brook no arguments from colleagues.
In 1992 he moved to his brandnew surgery in Market Street, where he began building the state-of-the-art practice of which he had dreamed.