With Vinegar and Brown Paper

A death on the motorway opens this one, and from it Maggie Forbes pulls a thread that leads to a man running for his life and a scheme built on forged bearer bonds. The man is Lambert, and he is afraid enough to abandon everything in a hurry, which tells Maggie more than any confession could. What follows is less a mystery than a slow reveal: everyone knows more than they are saying, and the bonds are the reason why.

The case then works the way these cases usually do. Nobody will admit to knowing anything. The paperwork is wrong in ways that take time to spot. And the people at the centre of it are the ones who look least like criminals, which is exactly why Maggie keeps digging. Steve Twolegs and Alan Dyer circle the edges, the Vicar and Steeple turn up with reasons of their own for caring, and Maguire watches the whole business with a patience that reads as menace. The motorway death turns out to be the first domino, and the episode is careful to show how each piece of the scheme depends on the last.

Ray Jenkins wrote it and Robert Fuest directed. Jill Gascoine's Maggie leads, with Nicolas Chagrin as Lambert, Malcolm Tierney as Maguire, J.G. Devlin as Steve Twolegs, John Forgeham as Alan Dyer, James Sport as DC Grant, David Rolfe as the Vicar and Walter Sparrow as Steeple, alongside Leslie Ash's Fred Smith and Rosalyn Landor's Pru Standfast.

The title, with its old folk remedy for a sprain, suits an episode about paper that looks innocent and isn't. Forged bonds are a quiet crime, and the show treats them that way: no explosions, just men sweating in rooms while their scheme comes apart around them. It is the quiet end of the crime world, and the show has a good feel for it.