Nidge is summoned back to Spain, where Terence demands a terrible price for his continued support, while Siobhan and Moynihan reach an unholy deal of their own.

Nidge uses Scotty as a driver on a new job, while Siobhan learns Tommy will soon wake from his coma and finds herself caught between her quest for revenge and her love for Pauley.

The truth about Paddy's night is out. Boxed into a corner Nidge contemplates a new life in Spain - but soon realises it's only a matter of time before Dano catches up with him.

In the aftermath of Pauley’s death Siobhan must face her most terrifying opponent yet as Terence May flies in from Spain to lay his nephew to rest—and to find the truth.

With Pauley’s help, Nidge is back in business and arrangements are made for the first shipment under the new deal. Meanwhile Moynihan wrestles with a labyrinthine Garda bureaucracy.

Moynihan's surveillance operation closes in on Nidge and Andrew's dummy run bringing in a shipment of mixing agent, while Fran plots a gruesome revenge.

Fran, still afraid that he could go down for the tiger kidnapping, lashes out looking for someone to blame. Resulting in a serious challenge to Nidge's authority.

Pressure builds on Nidge as the leaders of Dano's organisation send an inquisitor down from the north to thwart him, and matters only get worse as his lies start to catch up with him.

Darren is tracking Jimmy Byrne, the chief suspect in the gangland killing. But in the meantime he needs to work and he soon finds himself slipping back into working for gangland boss John Boy Power. In a world of paranoia and betrayal will Darren be able to keep his wits about him, kill Jimmy Byrne and find love again with Rosie?

Darren Tracey skipped Dublin when a gun was found in his house and he’s been living the past year in Spain, but he decides to risk it and come back to Dublin. He’s homesick and a party for his brother’s release from prison is the perfect excuse. It’s only for the weekend but sometimes life is full of surprises - especially if you and your friends are in gangland.

The crew are in festive spirits as Trish has the baby on Christmas Eve, while Rosie has come back to Dublin and Darren falls in love with her all over again. However the gang war is still raging, and John Boy orders Tommy – already caught between his friendship with Debbie and his worries about Siobhan’s money runs – to kill Fran. The hit goes wrong, and someone else becomes fatally caught up in the aftermath.

When a container of drugs is busted at the docks, John Boy decides to double cross Fran on their deal. Fran retaliates against John Boy. John Boy is furious and orders Nidge to pipe bomb Fran's house leaving Fran determined that the escalating gang war will not end until he has revenge.

Dublin gang boss Nidge has been blooded and has proved his mettle. He has killed friend and foe to become King. But the throne is a dark and lonely place.

The gang come back from Nidge’s stag party in Prague to learn that Jimmy Byrne is back in town. His friends think Darren should kill him as soon as, but Darren’s not so sure. Tension mounts as Darren needs to make decisions not only about whether to follow through on his suspicions, but about what he should do about his feelings for childhood sweetheart Rosie. As Darren grows closer to uncovering the truth, tensions and suspicions rise among the gang. Darren in particular faces difficult decisions about his feelings for Rosie, his future and his loyalties.

Nidge coerces his dentist into cooperating with him, unaware that Detective Inspector Moynihan is setting up a complex undercover operation to track and ultimately bring him down.

Fran is banged up in prison but he and Nidge both still conspire to have each other killed, while Siobhan finds her dangerous drug fuelled double life is spiralling out of control.