Episode 6

Siobhán Delaney is still trying to walk home from the mountains and Fran Cooney is burying his sidekick Dean in a shallow grave. Fran buys a gun with a wad of cash, intending to kill Nidge, and neither of them knows that Terence May has summoned Nidge to Spain. Terence, holding him responsible for the business after Pauley's death, tells him there is a rat and that something has to be done about it. He orders the murder of Janet, Nidge's mistress and brothel keeper, to set an example to the gang about talking to the Gardaí. Nidge is reluctant but does not prevent it. Janet is killed at her home, off screen; the Irish Independent's review understood the method to involve a bone-saw, though the recaps keep the detail vague.

The Gardaí dismiss Scotty, the undercover officer whose affair with Nadine compromised the surveillance, and Detective Ciarán Madden loses his temper at him before Scotty is ordered out of Ireland. Nidge returns home to Trish, who gives him a pair of runners monogrammed King Nidge. Aido cleans compulsively to stay off drugs; Nadine suspects him of having killed Scotty, and Nidge appoints her manager of the brothel. Moynihan, frustrated, pulls Nidge over, eats his car tax disc and beats him before colleagues pull him away.

At the brothel Nadine spots Fran pistol-whipping a passer-by and tips off the Gardaí; a car chase through Dublin ends with Fran recaptured and returned to Mountjoy, a capture the blog criticism called anti-climactic. Siobhán goes to Nidge and Trish's house, plants in the bathroom cabinet the finger bone she took from Fran's caravan so the Gardaí can tie Nidge to the murder of Git Loughman, then meets Nidge outside, confronts him about the beating that left Tommy in a coma, and confesses that she has been the rat all along and has given the Gardaí a statement and planted the bone.

In prison, Fran is cornered in the showers by Noely Hughes and his associates, who have waited for him since Nidge told Noely about the desecration of his mother's grave. He is held down and raped with the broken end of a cue and left lying in blood.

As the confession ends, Patrick Ward arrives at the house by van with a gun, ahead of the Gardaí. His first shots hit Siobhán, caught in the crossfire and left dying in the driveway. Patrick chases Nidge through the house and into the back garden, where Nidge is shot in the chest and falls and a second shot is fired into him at close range. He dies in front of Trish and their son Warren; Siobhán dies of her wounds. The programme's lead and its longest-running female lead are killed in the same sequence, by the same man, in the last minutes of the run. There is no arrest and no trial, because the Gardaí have a forensic case against a man who is already dead.

The finale's strength is the scene between Nidge and Siobhán, two characters who have circled each other for five series saying the true thing at last. Its weakness is its compression: the hour must resolve the Garda case, the Fran escape, the Janet order, the Terence relationship, the Scotty thread and the ambush, and both national reviews that disliked it said so. It ends the programme rather than the season. The finale drew an average of 1,005,400 viewers and a 56 per cent share, and at the 2015 IFTAs the series won Best Drama, Best Script for Stuart Carolan and Best Lead Actress for Charlie Murphy. RTÉ never made a sixth series. It is one of the three recommended hours, and the reason is structural: the show finally kills the lead it spent five years building, in the least cinematic place available to it, with no arrest, no trial and no redemption.