Trial & Retribution XVIII: The Box (2)

The second half of "The Box" spends its time unpicking the case against Ronnie Reid, and it does so by taking away everything that seemed to point at him. Anna's diary entries, which initially suggest Ronnie was stalking her, turn out to be forgeries. His alibi for the night Margaret disappeared holds up. Piece by piece, the frame around Ronnie starts to look like exactly that, a frame, and the likeliest hand on it belongs to his own brother.

There's something properly bleak about this. Kevin Reid needed someone to carry his guilt, and a simple lad with a speech impediment is the easiest sort of person to build a case against. Walker and Mullins work through the layers of deception with growing unease, and the episode lets you feel how nearly it all sticks. Wrong man, tidy evidence, everyone goes home. That's most wrongful convictions in miniature, and the show knows it.

It all comes to a head at a racecourse, where the brothers meet in a showdown that earns the word explosive without anyone firing a shot. Jamie Sives and Michael Nardone play the pair beautifully, Kevin's control set against Ronnie's hurt, and Hayman gets to be furious on Ronnie's behalf, which suits him.

Alex Pillai directs; no writer takes credit on this one, though Lynda La Plante's fingerprints are all over the machinery. David Hayman leads as Walker, with Dorian Lough as Satchell, David O'Hara as DC Jack Mullins and Kerry Fox as DI Moyra Lynch. Gugu Mbatha-Raw plays Jenny Miller, Robert Willox is Bill Hennessy, Judy Loe is Eileen Banks, Sheila Donald is Mrs Walker.

The first half asked who killed Margaret. The second asks a better question: who decided Ronnie did? Cases like this one don't get solved so much as taken apart, and watching it happen is why this series was worth following for over a decade.