Trial & Retribution XVIII: The Box (1)

Walker goes home to Glasgow, and it isn't a holiday. His mother is slipping into senility, and he's there to look after her, a man built for murder inquiries reduced to checking the locks and remembering the shopping. Then an old friend called Bill asks a favour. His sister Margaret vanished years ago, and a woman has just been in touch whose own daughter, Anna, has also gone missing. The thread running between the two cases is a man named Kevin Reid. Both women married him.

You can see where this is going before Walker does, and he's a quick man. Kevin had a brother, Ronnie, and the bond between the two of them is the dark heart of the thing. DI Jack Mullins handled Margaret's original disappearance and is bullish about it, in the way coppers are when an old case gets reopened by an outsider, but he lets Walker in on his findings all the same. David O'Hara plays him with just enough bluster to make the eventual sharing feel like a concession.

The body, when it comes, is Margaret's, and it's found in a large box minus its legs. That detail does the work of a dozen lesser shocks; the show trusts you to be appalled without being told to be. And then Kevin's second wife disappears too, which turns suspicion from one Reid to possibly both. Evidence in the research points toward Ronnie, a simple lad with a speech impediment, which raises the uncomfortable question of who was leading whom.

Lynda La Plante wrote it and Alex Pillai directs. Hayman is quietly excellent here, playing Walker off-duty but never off-guard. Kerry Fox turns up as DI Moyra Lynch, Jamie Sives is Kevin Reid, Michael Nardone is Ronnie, with Gugu Mbatha-Raw as Jenny Miller, Robert Willox as Bill, Judy Loe as Eileen Banks and Sheila Donald as Mrs Walker.

The Glasgow setting suits the show. Grim cases, grim weather, and a detective with his own grief to carry.