Hooked

Series five starts with Chappel in disgrace, or as close to it as the Met allows. His last investigation has ended badly enough that he has been put behind a desk, and into his place comes Chief Inspector Frank Vickers, drafted into the Vice Squad with a much-vaunted zero tolerance campaign and the manner of a man who plans to make it work. The unit is being reshuffled around him, and nobody is pretending it is an upgrade. The old guard watches the new broom and waits, which is usually the right move.

Then Hutchins goes missing. She has gone undercover into the world of a pornographer and the operation has swallowed her, and suddenly the desk-bound Chappel is the only one moving. He risks everything he has left to find her, which in his position means his job and his reputation, along with the small store of goodwill Vickers has not yet spent. The episode calls itself Hooked, and the title works two ways: the squad is hooked on the case, and Hutchins is the bait.

But it is a good engine for an opener. The episode gets to put its most trusted officer in genuine danger while its hero operates from outside the official lines, unwanted and uninvited. Tim Pigott-Smith's Vickers does the bureaucratic menace so well you almost forget he played the corrupt DS of the same name a series ago, and Caroline Catz makes Hutchins' disappearance feel personal rather than procedural.

The rest of the unit orbits the crisis. David Harewood's Robinson and Rosie Marcel's Morgan work the case from inside the squad, Stephen Kennedy's David Price circles the pornographer's world, and Mel Raido's Adam Parkes, Jackie Kane's Saira and the reliably named P.C. 1 and P.C. 2 fill out the ranks.

Rob Pursey and Barry Simner wrote it, Ashley Pearce directed. It is a strong, angry start to the final series, and it gives Chappel the one thing a desk job cannot: something worth leaving it for.