Double Bind (1)

Two things happen at once and the show knows exactly how they fit together. A badly decomposed body turns up buried in a Hampstead garden. At roughly the same time, a convicted murderer walks out of a secure psychiatric unit. He's been inside since 1967, when, as a teenager, he killed his own parents. And the body in the garden is one he's just told people where to find.

That's a strong hook for a cold case: the man who confessed to two murders forty years ago now hands the squad a third victim nobody knew existed. Either he's finally telling the truth about something, or someone is using him as an unreliable narrator to point the investigation wherever suits them. Double Bind takes its title seriously; everyone involved seems trapped between two versions of events, and part one enjoys letting each new fact make things worse rather than better.

Trevor Eve is DSI Peter Boyd, with Sue Johnston's Dr Grace Foley bringing the psychological reading of a case that's really about what was done to a child who then did something unforgivable. Wil Johnson is DI Spencer Jordan, Félicité Du Jeu is DC Stella Goodman and Tara Fitzgerald is Dr Eve Lockhart. The Lennon family history is carried by Greg Hicks as Chris Lennon and Joanna Hole as Gloria Lennon, with Miles Anderson as Daniel Lennon, Jill Baker as Dr Caroline Ritter and Hugh Mitchell as Mark Lennon.

Barbara Machin and Richard Warlow wrote it; Andy Hay directs.

1967 gives the story real weight. The psychiatry of the era, the institutions, the family secrets that stayed sealed because everyone alive preferred them that way. The episode moves briskly without rushing the material, and it trusts you to hold several possibilities open at once. An escaped killer who might be the only honest person in the case is a good place to leave things.