Unnatural Vices: Part 2

The second part of Unnatural Vices tightens the case around Chris Collins and settles the question the first part left open. Another victim disappears, and a severed finger is sent to Collins in an envelope — a deliberate communication rather than a gesture, and evidence that the killer knows who is investigating and how to reach him. The stolen whip from the S&M club, found in his girlfriend's flat, has already made him a suspect in the audience's eyes as well as the force's.

What the film does with that pressure is more interesting than a simple case of a compromised officer. Collins is being drawn into the investigation personally rather than professionally, and the show uses the correspondence with the killer to make him a participant in the crime rather than merely a target of it. The series had set up a long piece of character development across all four stories of the final run, and this is where the machinery becomes visible: Collins is not being investigated, he is being recruited, and the programme is careful to make the process gradual enough that his colleagues do not see it.

The investigation itself resolves the field the first part established. The mannequin-modelling husband, the psychiatrist and the school teacher are each accounted for, and the identification of the offender arrives through Hill's reading of the psychology rather than through any single piece of physical evidence, which is the series' standard route. The production's own synopsis promises "a twist in the tale", and the episode delivers one, though the published record does not describe it in the detail a reader might want.

The ending of this pair also establishes the series' overarching threat. This is the story in which Michael, the cannibal psychiatrist, is caught, and his existence drives everything the final run does: the official press material for the seventh series describes Hill's battle with Michael as the backbone of the eight-week schedule, and that battle begins here. Jolyon Baker plays him with a quiet professional composure that makes the later escapes more alarming than a more obviously unhinged performance would have done.

What is weaker is the resolution's speed. The two-part format gave the series more room for parallel cases and slower revelation, but within a single story the second hour still has to close everything, and the compression shows in the last twenty minutes. An audience that has been given three named suspects is likely to find the elimination of two of them brisk.

It drew 5.11 million viewers and is rated 8.1 by IMDb users, higher than the first part. It is the most plot-driven of the four two-parters and the least self-contained, and it is best understood as the first and second movements of the series' final statement rather than as a story in its own right.