Harry Da Souza is called upon to make a problem disappear after a night out goes awry for the sons of two warring crime families. As boss Richie Stevenson looks to pin blame, patriarch Conrad Harrigan gathers his clan with a plan.

Harry deals with the aftermath of the Harrigan family meeting as Jan wonders what's the final straw. Kevin scurries Eddie out of London after a threat from Richie. Maeve shows her hand to Conrad. Chasing a lead, Harry makes a startling discovery.

Richie makes his move, putting the Harrigans on high alert. Conrad and Maeve lock horns over Eddie but agree on a plan B. As Kevin prepares for all-out war, Harryhugs two birds with one stone, and an anonymous tip leads Fisk to the cemetery.

Harry pays a visit to Antoine at the urging of Bella. Fisk and Mukasa trade theories. Suspecting a rat, Conrad comes to Jan for a favor. Kevin makes a startling confession. Richie calls a midnight meeting at the Sinful Monkey with shocking results.

Kevin and Harry assess scenarios in a search for insurance and an exit strategy. Looking for a way back in, Brendan approaches Seraphina. Left to their own devices, Bella and Jan commiserate. Richie makes a proposal. Maeve, in her element, strikes.

In the aftermath of Plan B, Conrad twists the knife and Fisk has a realization: this is war. Maeve gives Eddie a lesson in the art of chess. Richie takes the bait. Harry goes searching for Seraphina and Brendan, who've gone rogue.

O'Hara points out the elephant in the room. Harry takes extreme measures.

Maeve extends an olive branch and Kevin questions the wisdom of a sit down with Jaime. Tattersall offers Fisk and Mukasa a new point of entry. Harry comes to Kat for a favor as Richie, at the Sinful Monkey, contemplates a new affiliation.

Bella does a runner to London. Tattersall gets Alice's tootsies tapping. Kevin confronts his past. The Harrigans sit down for a normal family dinner.

Kevin takes care of a problem. Tattersall delivers on a promise as Richie prepares for war. Seraphina, reading the room, agrees to a meet and greet. Maeve spills the tea. Jan gets Harry's attention. Season finale.