Season 2 concluded with Sully's actions rewriting the rules of his business with Dushane. Now, the two of them will endure new problems as everything they've built comes under threat from forces outside and within their empire. The rules that Sully and Dushane have lived by their whole lives are tested in an ever-changing world in a final chapter that will decide who can reign as Top Boy of Summerhouse.

Dushane wants to expand his empire beyond the streets. But with a huge investment, partners abroad and family crises, more money means more problems.

Two seasoned drug dealers return to the gritty streets of London, but their pursuit of money and power is threatened by a young and ruthless hustler.