In the half-century since the crimes of Ian Brady and his accomplice Myra Hindley sickened all in Britain who learned of them, the relatives of their five victims have reached a resolution - a qualified one, it must be emphasised - with the recovery of bodies, some with the cooperation of the imprisoned pair, and burials and prayers for their lost children.
Ian Brady has been a figure of horrified fascination for the British public, for nearly half a century
All except one family, that of Keith Bennett, murdered four days before his 12th birthday in 1964 and buried somewhere on Saddleworth Moor. In all the time since, his mother Winnie Johnson begged Brady to reveal his whereabouts, but she died earlier this week without getting the answer she lived for.
This documentary had three aspects to it. The first was the dignified, palpable, continuing pain of the victims' relatives, waiting for Brady to die, while realising that chances of finding Keith would probably go with him. As one commented with heart-breaking irony, "We can't beat it out of him."
Meanwhile, experienced professionals tried their hardest to explain his actions, both during the time of the murders - building a bubble of a cult with Hindley - and ever since.
According to them, it all comes down to control, whether that involved Brady pouring excessive salt on his food, leaking information about Hindley's complicity when it looked like she might get parole, to even pretending to help police search for Keith Bennett's body on the moor when, one psychologist speculated, he was, in fact, enjoying his secret knowledge.
His former solicitor Benedict Birnberg offered that it was his pent-up anger that had kept him going so long, while Religious Studies teacher Dr Alan Keightley, who used to visit Brady, was scathing in his descriptions of how these experts would fail to understand their patient - "he's been doing this for 40 years," he scoffed.
Two things stood out in this documentary. The first was the extraordinary timing of film-maker Paddy Wivell's attempt to chronicle Brady's 13-year hunger strike, just as Brady's health went into decline in July. And the second was that this brought Wivell into contact with the prisoner's mental health advocate of 15 years, Jackie Powell - a disturbing screen presence, and the best hope anyone has of understanding Brady these days.
Winnie Johnson, the mother of Keith Bennett, died without ever discovering the whereabouts of her son's body
A month before Winnie Johnson's death, Jackie Powell revealed straight into Channel 4's waiting lens details of a letter from Brady, proporting to be the information Winnie desperately craved.
Powell's ambivalence about her responsibilities was actually the most interesting part of the whole programme. While admitting that the psychopathology of someone like Brady meant his behaviour is intrinsically based on power and control, she found distasteful Wivell's language of Brady's "victory dance".
And while she remained unsure about the contents of the letter, and stuck to her professional guns in keeping the letter sealed (before eventually returning it to Brady so Wivell took it upon himself to inform the police), she admitted, too, this whole dilemma could be why she had it, ie that she was being tested, or played, herself.
Jackie Powell's ability to do her duty relies on the very detachment she displayed towards Brady and his crimes. Nevertheless, as her job develops under the camera's nose, with her power of attorney responsibilities, it must be strange for her, knowing she is one of the very, very few to care for her patient's welfare.
Wivell cleverly gave her enough screen time to explain herself, and you had to admire her robustness in the face of what must be exceptionally gruelling at times. It's a bitter pill to swallow that, if justice is to be served, we need people like Jackie Powell to protect even people like Brady. And her staunch position - that anybody, whatever they've done, is deserving of human rights - must force us to ask questions of ourselves that we can't always answer, particularly when the sweet, sad face of Winnie Johnson is at the forefront of our minds.