Under his leadership, the Peaky Blinders have risen from a local Birmingham street gang to a national enterprise that has gone toe-to-toe with the New York Mafia.
He has great remorse over his actions, but he cannot always control himself, as he gets aggravated easily, especially over things that, as he feels, are meant to attack his or his family's pride.
By the end of 1924, however, Ada assumes a leading position in the United States branch of Shelby Company Limited, dealing only with legal acquisitions, unlike her brothers in Birmingham.
Grace Helen Shelby (née Burgess) (played by Annabelle Wallis) was an Irish woman who takes up employment as a barmaid at The Garrison Pub, and secretly operated as an undercover agent for the Birmingham Police.
Chester Campbell (played by Sam Neill) was an inspector in the Royal Irish Constabulary hired by Winston Churchill to locate and recover the missing consignment of guns from the Birmingham Small Arms factory.
He hires Inspector Campbell to retrieve his stolen machine guns, a man who he finds amusing but a good candidate for the job.
After Thomas learned about Polly's wish to find her children again, he pays Michael's foster family a visit and invites the boy to see his biological mother.
Freddie Thorne (played by Iddo Goldberg) was a known communist who lived in Birmingham and was formerly a close friend of Thomas Shelby.
Upon finding out that Billy was the one who informed the IRA about the attempted assassination of Oswald Mosley, resulting in the operation being ruined, Isiah and Duke beat him.
A shaken Finn shows his true colors by furiously insulting Duke's mother and turning the gun on Isiah.
Alfred "Alfie" Solomons Jr. (played by Tom Hardy) is a Jewish gang leader residing in Camden Town, London.
William "Billy" Kimber (played by Charlie Creed-Miles) was an English gangster and head of the Birmingham Boys, the main enemy of Thomas Shelby and the Peaky Blinders.
Thomas makes her his secretary, but not only does he expect her to play the whore for him when his plans require it, the family refuses to allow her any say in who she dates or what does in her off-hours.
Father John Hughes (played by Paddy Considine) was a member and representative of The Economic League, working with Patrick Jarvis.
Hughes represented the Crown and was acting under orders to report to the Reds because they wanted to provoke an attack on British soil, which would break diplomatic relations with the Communists.
Aberama Gold (played by Aidan Gillen) was a Romany gypsy hitman-for-hire, a man with a reputation for being a dangerous savage with little regard for the rules.
Jessie is a union leader at one of Thomas Shelby's factories and is a member of the Stechford branch of the British Communist Party.
They are protesting at poor conditions, lack of holidays, unsanitary lavatory provisions, and lower pay for female workers.
Jimmy McCavern (played by Brian Gleeson) is the leader of the Billy Boys and a member of the Glasgow razor gang.
He was admitted to a mental asylum shortly after the war after committing an unknown crime, presumably due to his severe shell-shock and was certified insane.
Barney was key in the assassination attempt on Oswald Mosley at a rally at Bingley Hall, tasked with sniping him on stage from a lighting control room.
Jack Nelson (played by James Frecheville) is an Irish-American gangster with ties to high-level politicians, such as President Roosevelt.
Laura McKee (also known by her alias Captain Swing) (played by Charlene McKenna) was a leading member of the Irish Republican Army, Battalion Commander of Fermanagh branch.
Billy Grade (played by Emmett J. Scanlan) was an Irish retired professional footballer who becomes a singer in the Garrison Pub.
Jack Nelson violently forces Billy to act as his informant on the Peaky Blinders so he can have Arthur Shelby killed.
He is seen when Billy storms into the Garrison Pub and confronts the Shelby Brothers about fixing the horse races which Kimber runs.
Jeremiah "Jimmy" Jesus (played by Benjamin Zephaniah) is a Jamaican born street preacher, who is friends with Thomas Shelby and the Peaky Blinders.
May Fitz Carleton (played by Charlotte Riley) is a wealthy widow who owns racehorses, and is enlisted by Thomas Shelby to train his horse for Epsom.
Ben Younger (played by Kingsley Ben-Adir) was a colonel and head of army intelligence officers who arrived in Birmingham and arrested Ada Shelby over her communist past.
Hayden Stagg (played by Stephen Graham) is a union convenor who is stealing some of the opium in storage at the Salthouse docks in Liverpool.