The leader of a criminal gang in Birmingham, the Peaky Blinders, consisting of members of the Shelby family.

A lover of horses, whiskey and tobacco, a real shark in the criminal world. He has a strong character, a thirst for adventurism, cruelty and the characteristic coldness inherent in people of his business.

Thomas Michael Shelby was born in 1890 to Arthur and Mrs. Shelby. He was born on a ship, in a barge called January, and he had an older brother, Arthur Shelby, with whom he was very close as a child. Over time, Thomas's parents had three more children — John, Eida and Finn Shelby.

Thomas' parents were Gypsies, so he and all his siblings were also full-blooded gypsies. Thomas's paternal aunt, Polly Gray, hints that the Lee family is related to the Shelby family through their mother. They are also descended from Irish Travelers, because Polly mentioned that along with Gypsies, they should not speak the Shelta language next to Carl Thorne, which is spoken by Irish Travelers. It is also implied that their father was partly an Irish Traveller.

When Thomas was growing up in Small Heath, Birmingham, he carried a knife and a screwdriver with him and told other kids in the neighborhood that he could cast curses, so they were afraid of him and didn't pick on him or tease him about it. Thomas and his siblings had to buy their father's beer at the Garrison. However, because they were so small, the two of them had to carry one bucket to their home. Thomas also fought with his brothers over cigarettes, and once, when Thomas was 9 years old and Arthur was 12, they had a big fight. Thomas pinned Arthur to the ground and began hitting him several times on the head, subsequently winning the fight, although Thomas admitted that Arthur had allowed him to win.

Thomas Shelby is a former British soldier, his military ID states that he fought bravely in the "Battle of Verdun" and the "Battle of the Somme". His actions at Mons reportedly saved thousands of Allied lives, for which he received honorary medals after the war, including the Military Medal and the Distinguished Service Order.