The 1940s, at the height of the Second World War. Many years later, Tommy Shelby, the head of one of the most dangerous street gangs, returns to the bombed Birmingham where he left his son. The son has followed in his father’s footsteps, and now he is involved in a secret conspiracy. Shelby faces the toughest test of his life, when the fate of his son and the future of the entire country are at stake.