The Shelbys suffer a crushing loss. Four years later, Prohibition's end turns Tommy toward the opium trade, forcing him to ally with his worst enemies.

Series five finds the world thrown into turmoil by the financial crash of 1929. Opportunity and misfortune are everywhere. When Tommy Shelby MP is approached by a charismatic politician with a bold vision for Britain, he realises that his response will affect not just his family's future but that of the entire nation.

December 1925. Tommy Shelby OBE has acquired unprecedented legitimacy.
The former gangster is also a man alone, estranged from his family and focussed only on business. But when he receives a mysterious letter on Christmas Eve, Tommy realises that the Shelbys are in danger of annihilation.
As the enemy closes in, Tommy flees his country house and returns to the only safe place he knows: Small Heath, Birmingham, the slum where he grew up. Facing a more determined and sophisticated threat than ever before, the Shelby family must find a way to put differences aside, work together, take up arms and fight for survival…