Based on the real Peaky Blinders gang that roamed the streets of Birmingham in the early 1900s, this series follows the operations of gang leader Thomas Shelby and his family as they navigate their way to becoming one of Britain's most formidable crime syndicates.

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As they embark on their quest for power, the Shelby's continue to encounter some of the most fearsome foes around from both sides of the law. Let's take a look at some of the most threatening cops, gangsters and Shelby kin to roam the streets throughout this series.

10. John Shelby

John Shelby from Peaky Blinders with a rifle slung over his shoulder

The third of the Shelby brothers, John admired and embodied the Peaky Blinders image in its entirety, from the way that he dressed to the way he conducted business. This together with his temper and physical strength made him a force to be reckoned with.

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His violent tendencies include severely beating Angel Changretta after his father confronted the Shelby brothers about Angel's shop burning down, as well as having a hand in beating Grace's murderer to death with his bare hands.

9. Arthur Shelby

Unlike his brother John, Arthur has no control over his flaming temper due PTSD induced by his experiences during World War I. This has resulted in him committing excessively violent acts without any signs of restraint, which has lead the others relying on him as muscle.

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Some of his violent acts include punching a young man to death during a casual sparring session in the Peaky Blinders boxing gym, and beating Russian refugee Anton Kaledin nearly to death, only to kill him by gunshot.

8. Polly Gray

The matriarch of the Shelby family and Shelby Company treasurer, Polly is Thomas's closest confidant and temporary head of the organization during the war. While she may not be physically imposing, she can harm her enemies in many other ways due to her position of authority and knowledge of many secrets.

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She did well to intimidate Grace during a heart-racing scene after finding out her true mission, and eventually murdered Inspector Campbell when he pushes her too far.

7. Chester Campbell

Sam Neill as Campbell in Peaky Blinders

The Chief Inspector hailing from Belfast, Winston Churchill himself sent Campbell to Birmingham to locate a crate of guns in the possession of the Shelbys and rid the city of crime.

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Campbell had much pull in the police department, and managed to pull off many raids, including one at The Garrison Club owned by the Shelbys. Furthermore, he managed to pressure Thomas into cooperating with him by arresting numerous family members including Arthur and Michael.

6. Billy Kimber

Head of the Birmingham Boys, Kimber controlled the race courses in the regions of the Midlands and the North, possibly making him the biggest organized crime boss in the country.

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He was the greatest rival to the Peaky Blinders in the show's first season and had a great number of men and weapons at his disposal. If not for the Shelbys' machine gun and some quick thinking from Thomas and Ada, Kimber may have eliminated the Peaky Blinders in their entirety.

5. Darby Sabini

The head of an Italian Gang based in London, Sabini was regarded as the king of the racecourses due to running most of the races in London as well as the South of England at large. He was as proud as he was powerful, and if anyone came looking for trouble, he would always hit back with a vengeance.

Thomas Shelby learned this the hard way when Sabini and his men came within an inch of beating him to death after the Shelby brothers attacked the Eden Club. He was also crafty and managed to temporarily convince Alfie Solomons to cooperate with him against the Peaky Blinders.

4. Aberama Gold

When threatened by the Italian New York Mafia, Thomas Shelby knew that he needed to request help from the most ruthless hit men around. While the Lees are reliable allies for the Peaky Blinders, Thomas decided to rather reach out to Aberama and his men, who proved their killing efficiency during John's funeral.

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What makes him even more deadly is his utter disregard for rules. He has even gone so far as to shoot police officers during his mission against Luca Changretta.

3. Luca Changretta

Luca looking surprised in Peaky Blinders Season 4

A member of the frightening New York Italian Mafia, Luca was the oldest son of Vicente Changretta, who sought revenge on the Shelby family for what they did to his brother Angel.

He sent shivers down the spine of the Shelbys by sending them the black hand, thereby marking them for death. His men were successful in assassinating John and hospitalizing Michael soon after.

2. Thomas Shelby

Thomas Shelby hallucinates about Grace in Peaky Blinders

The leader of the Peaky Blinders, Thomas has proven himself to be a force to be reckoned with in all areas. He defeated many foes in physical combat, including Luca Changretta and assistant chef and assassin Antonio, and has proven to be a master negotiator, brokering deals with the likes of Inspector Campbell and Alfie Solomons.

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Even more impressive is his business acumen. Despite the pressure of the organized crime world, Thomas was still able to acquire a legal racetrack operation as well as numerous factories and properties.

1. Alfie Solomons

A leader of a Jewish gang in London, Alfie heads up a distillery under the guise of a bakery. He ran a largescale operation and was at war with Sabini and the Italian gang. This feud prompted Thomas to enter into business with him as a means of coming to London.

He is prone to quick acts of violence, such as when he handed Arthur to the police and shot Billy Kitchen dead. Sabini, noticing Alfie's strength, approached him to make peace. However, one more betrayal saw him fall out of favor with Alfie yet again, as Alfie recommenced business with Thomas.

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