Trial & Retribution XVII: Conviction (1)

Terry Dyer walks out of prison still saying he didn't do it, which is the sort of line you hear in every prison drama ever made. Here it happens to be true. He served time for killing Mark Randle twelve years ago, and within moments of getting back to his East London estate he's face to face with Ken Randle, the boy's father, who has spent those twelve years hating him with the clean certainty of a grieving man. Ken confronts him and draws blood. Walker, to his credit, treats the old man as what he is, a recovering alcoholic at the end of his rope rather than a villain, and lets him out on bail.

The case starts coming apart almost at once. Dyer has always claimed the real killer was Nick Fisher, the man Mark caught with his sister Sarah, who was thirteen at the time. Awkward enough. Then Nick Fisher turns up dead himself, and his widow picks Dyer out as the figure loitering near her husband's workplace. Open and shut, you'd think. Except CCTV puts Dyer miles away when it happened, and Ken begins wondering whether a friend of his son's, someone older, someone trusted, was there on the original night. Long-buried things start surfacing, as they always do in this show, and DS Satchell finds his career wobbling underneath him, which is never a comfortable place to stand.

It's a good opening half, patient where it could have been loud. The grief of Ken Randle, played by Maurice Roëves, carries more weight than any plot twist, and Johnny Harris makes Dyer's cornered decency feel earned rather than assumed. Tom Ellis gets a brief, unhappy turn as Fisher.

Julie Dixon and Lynda La Plante wrote it, Paul Wilmshurst directed. David Hayman's Walker and Victoria Smurfit's Connor hold the centre, with Dorian Lough as Satchell, Kierston Wareing as Leigh Fisher, Lorraine Perez as Sarah and Aimee-Marie Bow as young Sarah.

What stays with you is Ken, a father discovering that revenge needs a target who deserves it.