Episode 3

The case is an occult killing, and it starts badly. A woman is taken by a man who leaves her baby behind in the living room, which tells Luther everything he needs to know about the kind of person he is chasing. The child is safe. But the mother almost certainly is not.

Luther builds the case while the clock runs down, and the episode makes sure nothing comes easily. A man comes forward claiming Luther attacked him during the pursuit, and the accusation lands at the worst possible moment, when the department is already watching the detective sideways. Then the woman is found, and the grisly end of her story closes off the hope that this could have been a rescue. What is left is a conviction, and Luther is told to build an airtight case with a young mother's life in the balance.

Neil Cross wrote the script and Sam Miller directed, and the cast gives the grim material some weight. Paul Rhys plays Lucien Burgess, the kind of quiet, controlled presence the show is good at producing, and Catherine Hamilton's Kirsten Ross is the victim whose fate hangs over everything. Around them Saskia Reeves's Rose Teller, Warren Brown's Justin Ripley and Steven Mackintosh's Ian Reed do the departmental heavy lifting, with Andrew Tiernan's Richard Henley, Ruth Wilson's Alice Morgan, Indira Varma's Zoe Luther and Paul McGann's Mark North filling out the edges.

It is not an episode with much daylight in it. The occult trappings are handled without silliness, and the horror stays in the details: the empty cot, the wrong kind of patience in the killer's manner. Luther's own judgement comes under fire at the same time as the case, and the two pressures push him toward the sort of corner he tends to fight his way out of.

The episode ends with the job half done, and the certainty that the next one will be no easier.