Rose’s vanishing affection led to West shifting tactics. “There is a notion that people have, that he wasn’t very bright,” says Ogden. “Well actually he was quite cunning and quite manipulative, and seeking to turn things around to his benefit.”

His defence unravelled yet further a week after being arrested, when West told a legal clerk that there were a “f---ing load more” victims, and wrote a note confessing to “approx nine further killings”. Russ Williams, then-Detective Constable at Gloucester Police, “thought to myself when the note was read out: how do you not know how many people you’ve killed? It’s not as if somebody’s asking you how many cars you ever had. I mean, how could you forget?”

From that moment on, officers worked up to 16 hours a day on the case, combing through the mountains of leads from their own investigation and those generated by the global media scrum, which was by this stage “carnivalesque”.

Williams, 60, remembers West as “charming”, appearing to be “very much in control of the relationship between him and Rose.” But as time wore on, it became apparent that “Rose was the dominant partner and [responsible for] decision-making.” While her husband was in prison for theft in the early 1970s, Rose murdered Charmaine, his eight-year-old daughter from his first marriage. Fred West had already killed Charmaine’s mother, Catherine “Rena” Costello, and Ann McFall, their 18-year-old nanny, who was carrying West’s baby when she disappeared in 1967.

It is unclear whether Rose knew what he had done, but in his second wife, West had seemingly found someone more like-minded. “The desire for sexual gratification, the abuse, the lifestyle that they led… they had clear objectives; joint objectives about what they wanted to do,” says Williams.

Digging for Heather’s remains turned up three thigh bones, the first conclusive proof that there were more bodies. Remains kept coming: those of 17-year-old lodger Shirley Ann Robinson, who was eight months pregnant with another of West’s illegitimate children; Alison Chambers, 16, who West claimed not to know by name.

When I ask Dezra Chambers how she feels about West referring to her sister only as “Shirley’s mate”, it is the first she has heard of yet another cruel insult to unthinkable injury. Alison, younger by two years, “was intelligent; she loved doing her hair. She could play chess, she had lots of friends, a bit of a rebel,” Chambers, 64, remembers. “She was lovely”.