The disappearance of Heather West, Frederick and Rose West's eldest daughter, led ultimately to the Cromwell Street murder inquiry, Winchester Crown Court was told yesterday.
Brian Leveson QC, for the prosecution, told the court: "In June 1987, when she was 16 years old, she disappeared. Her parents did not report her missing. The reason is simple. They knew that she was dead because both had been involved in killing her.
"Rosemary West, this defendant, was interviewed by the police. She said that she had heard from Heather on the telephone. The authorities continued looking and on 24 February 1994, armed with a search warrant, they returned to 25, Cromwell Street."
He said that they unearthed Heather West's bones under a patio in the back garden two days later. The head had been severed and the bones had been chopped up to reduce the space in which the skeleton could be buried.
"The police continued digging and what they found was more terrible than words can express. Over the days which followed, the skeletal remains of eight other young women were found, each under the ground at the home of Mr and Mrs West."
Thus began a huge investigation for Gloucestershire Police which discovered that girls who came and went to 25, Cromwell Street over the years had been subjected to "violent and degrading sexual activity".
Mr Leveson said that it was not suggested that Mrs West had acted alone. As far as all 10 murders were concerned, she acted together with Frederick West, her husband, who was found dead in his prison cell on 1 January this year.
Mr Leveson told the jury that Rosemary Letts met Frederick West in 1969 when she was 15 and he was 27. They began a relationship and their daughter, Heather, was born in 1970 when they moved with Fred West's other two children to a ground floor flat at 25, Midland Road, Gloucester. In November that year, Mr West was sent to prison for 10 months for dishonesty. Mr Leveson said: "At the age of 17, it cannot have been easy for Rosemary West to cope with Charmaine, only 10 years younger, Anne Marie, who was six, and baby Heather in a small flat."
Mr Leveson said that it was impossible to precisely date when Charmaine vanished but when people asked about her whereabouts, they were told that she had gone to Scotland with her mother.
On 25 April, 1994, the police extended their search from Cromwell Street to Midland Road, where they discovered a skull and bones which were later identified by experts as being those of Charmaine.
In January 1972 Frederick West married Rosemary and later that year they moved to Cromwell Street, where they lived for the next 22 years. Mrs West had seven more children.
Mr Leveson said that the Wests picked up a 17-year-old girl called Caroline Owens who was hitchhiking to Tewkesbury in the autumn of 1972.
During the journey the Wests offered Miss Owens a job as their nanny and she accepted and moved in to Cromwell Street. After a few weeks Miss Owen left but in December 1972 the Wests once again picked her up when she was hitch-hiking. Mr Leveson said: "As they left Gloucester, Rosemary West put her arm around Caroline Owens and started talking of sexual matters. She tried to kiss Caroline on the mouth and began to touch her hair and fondle her breasts."
Mrs West then sexually assaulted Miss Owens and Mr West stopped the car. He then punched her in the face knocking her senseless and when she came round she was being tied up and gagged.
"Thus gagged she was driven back to Cromwell Street with Rosemary West holding her down and continuing the assault upon her. She was bundled indoors and taken to the first-floor front bedroom. The tapes were cut free. She was stripped naked and was laid on the bed, Mrs West touched her vaginal area, she struggled and her hands were once more tied up behind her back. She was subjected to a series of sexual indignities."
The following morning Miss Owens was released after promising not to tell what had happened but she reported it to the police and the Wests were arrested. They were subsequently charged with assault occasioning actual bodily harm and with indecent assault and on 12 January 1973 they were fined at Gloucester magistrates court after pleading guilty to both charges.
Mr Leveson then told the horrific story of how a series of girls were murdered after being held captive and sexually abused. The first victim was Lynda Gough, 19, from Gloucester.
Miss Gough, a seamstress, left home suddenly on 19 April, 1973. Her parents did not hear from her and began to make enquiries which led her mother to Cromwell Street, where Mrs West told her that Lynda had gone to Weston-Super-Mare.
"The Crown contend that she had been murdered and buried in what had been an inspection pit in a shed or garage. There she stayed for nearly 21 years until 7 March, 1994.
The body had been dismembered and many of the bones were missing. Near the skull was a ring mask of wound adhesive tape, two loose pieces of tape, a length of string and some knotted fabric.
Mr Leveson said: "The circle of masking tape found with the remains provides the clearest evidence that she was naked but gagged." Mr Leveson said that another five victims were buried in a circle in the cellar of 25, Cromwell Street, clockwise in the order of their deaths over the next 18 months.
The first victim was Carol Ann Cooper, who was 15 when she disappeared. In November 1973, on a visit to her grandmother in Worcester, she ended up in Cromwell Street. Her remains were found on 10, March, 1994. She had been decapitated and dismembered.
The next victim of the Wests was Lucy Partington, 21, a student at Exeter University. In December 1973, she went home to Cheltenham for Christmas and went to visit a school friend.
She left her house just before 10.15pm on 27 December to catch the last bus home. She was never seen again and more than 20 years were to pass before her remains were discovered under the cellar floor at 25, Cromwell Street. She had been decapitated and among the bones there was a kitchen knife.
The next victim was a 21-year-old Swiss Therese Siegenthaler, who was studying sociology in London.
She was last seen when she set out to hitch-hike across England. She was never seen again and on 5 March, 1994, her remains were unearthed in the cellar of the Wests' home.
Shirley Hubbard, 15, a girl from a broken home went missing in November, 1974. Her remains were found at Cromwell Street on 5 March, 1994.
The last of this group of victims was Juanita Mott, 18, a rebellious girl who came from a broken home in Gloucester.
During 1974 she used to visit 25 Cromwell Street, but later left to live with friends. Her remains were found in the cellar in March, 1994. Like the others, she had been decapitated and dismembered and there was a plastic- covered rope wrapped around her bones and a band of fabric around her skull.
Mr Leveson said that one victim of the Wests who survived sexual abuse was a woman referred to in court only as Miss A. In 1977, aged 15, she ran away from a Gloucester children's home and visited Cromwell Street.
Six weeks later she returned and was taken into a room where there were two naked girls. She was then undressed by Mrs West and sexually abused before Mr West had sexual intercourse with her.
Afterwards the Wests let her go and, said Mr Leveson, "obviously made an assessment that this girl would not go to the police". She only revealed the incident after the bodies were discovered.
Shirley Anne Robinson, 18, was a lodger and had an affair with Mr West by whom she became pregnant. She was last known to be alive on the 9 of May, 1978. Sixteen years later her remains were found in the back garden of 25 Cromwell Street. The body had been dismembered and decapitated and with the remains were those of a foetus of about eight months gestation.
Alison Chambers, 16, was a typical West victim. After her parents' marriage failed, she was taken into care and in January, 1979, was transferred to a children's home in Gloucester.
During that summer she was seen to visit 25 Cromwell Street on several occasions: on 28 February, 1994, her remains were found in the garden.
The Wests' last victim was their own eldest daughter, Heather, who disappeared in 1987, aged 16. After she disappeared, the Wests gave various explanations as to why she had vanished.
But Mr Leveson said: "Heather did not leave home. She was murdered and buried naked in the garden. None of her possessions were recovered, none of her clothes, none of her belongings - not a trace."