Thomas Shelby's war with the Lee family of gypsies escalates, and Campbell puts further pressure on him to deliver the stolen guns. Meanwhile Thomas's brother John plans to marry a former prostitute, but Thomas suspects that she's still on the game.

Thomas Shelby has to deal with an IRA chief who has come to Small Heath to avenge his cousin's death. Meanwhile Campbell gets closer to the stolen guns, and Grace has to decide whether her loyalties lie with him or with Thomas.

As Thomas Shelby prepares to oust Billy Kimber, hidden secrets are revealed and the family have to face up to the problems that have divided them. Meanwhile, Campbell, obsessed with taking down the Peaky Blinders, unleashes one last plan to destroy them.

Business is booming for the Peaky Blinders, as Shelby starts expanding both his legal and illegal operations. He plans for the future, looking at managing a race track in the South. He soon comes across some new adversaries, testing him in very different ways. Back in Birmingham, Shelby's home town is challenged by members of his family reacting to the upturn in their fortunes. A enemy from his past also returns hoping to exact their plan of revenge of biblical proportions.

Tommy offers to help Polly by searching for her children, who long ago were taken from her. In London, Tommy risks his life by meeting enigmatic leader Alfie Solomons. Meanwhile Arthur continues to feel the devastating effects of the Great War.

Arthur leads the Peaky Blinders takeover of London's Eden Club. Sabini decides to put old feuds to one side, convincing Alfie to one side to get rid of the Peaky Blinders. Tommy hires May Carleton to train his race horse, and the pair become fast friends. In Birmingham, Michael joins the family firm, hoping to help Tommy's businesses become more legitimate. Whilst Tommy's insecurities are intensified as he discovers what Major Campbell wants him to do.

Arthur and Michael both end up arrested and imprisoned. As Tommy's base in London is obliterated. Major Campbell has Tommy and his family under his thumb. Polly compromises herself hoping to secure Michael's freedom, but their relationship may be beyond repair at this point. Someone from Tommy's past pays him a visit, opening old wounds and leaving him to make a impossible decision.

As derby day arrives, Tommy is faced with impossible decisions as he plans to strike back at his enemies and take the family business to another level. Meanwhile, Major Campbell has one final card to play - one that he is certain will bring about Tommy's demise.

Thomas Shelby’s wedding day has arrived at last, but while his guests enjoy the celebrations he has important business to conduct, as a mysterious stranger makes their presence known.

Tommy goes to London to meet the wildly eccentric and volatile Duke Leon and soon discovers the extreme lengths his new paymasters are willing to go to in their quest for power. In Birmingham a personal dispute with the Italians threatens to explode into a devastating war.

Tommy takes his brothers on a hunting expedition and shares some important family news. He also outlines his intentions for the most daring criminal act the Peaky Blinders have ever undertaken.

As Tommy prepares to commit the most audacious crime of his career, an unexpected blow is struck, putting him under unbearable pressure. As he faces his worst fears he needs help more than ever, but is increasingly uncertain about whom he can trust. In a nerve-shredding race against time, Tommy is forced to confront hard truths about himself and his family that could change the Peaky Blinders forever.

December 1925. When Tommy receives a mysterious letter on Christmas Eve, he realises that the Shelbys are in danger of annihilation.

As the Shelbys come to terms with the shocking events of Christmas Day, Tommy endeavours to unite his family and a bold new enemy makes his move.

Faced with devastating news, Tommy goes on a quest to discover who it was that placed a curse on his family. In Birmingham, Ada takes charge, and Arthur takes on some new recruits.

Tommy establishes a connection between crime and political power that could alter the course of history. He also receives life-changing news from an unexpected source.