Fans Have a Few Intriguing Theories About the Peaky Blinders Season 5 Finale

Warning: Spoilers ahead for season 5 of Peaky Blinders. Stop reading now if you haven't seen the season yet!

This season of Peaky Blinders was exciting, heartbreaking, and even humorous—remember when Arthur tried to lead his first meeting as chairman of the board? However, nothing shocked fans more than the final episode of the season.

Tommy planned to assassinate fascist politician Oswald Mosley at a rally with the help of his old war pal Barney. Aberama Gold also planned to use the rally to settle a score he had with Jimmy McCavern, leader of the Billy Boys.

Everything was in place, and it looked like Tommy's plan was going to work...until someone was tipped off about the assassination plot, and both Barney and Aberama were murdered. Arthur was also ambushed, but he was able to overpower his attacked. However, it seems like Mosley still has no idea how close he was to getting killed.

Sam Claflin as Sir Oswald Mosley

The final scene of the season showed Tommy having a vision of his dead wife, Grace, and his dead horse, Dangerous. Tommy then puts a gun to his head and screams, but the scene fades to black before we can see what happens next.

We still have no idea who tipped who off about the plot, but fans have some theories about who it could be.

Billy Grade

Billy was a soccer-player-turned-singer-turned-forced-employee of the Peaky Blinders, and while he seemed to come to enjoy his role fixing matches for the Blinders, Arthur seemed suspicious of him. And when Finn spilled to him that "a fascist is going to get killed tonight," we immediately saw Billy reach for a phone.

Michael and Gina

After being accused of plotting against Tommy, Michael and his new wife Gina were ostracized by the rest of the family. And while Michael was later forgiven, things only got worse when the new couple outlined a plan where they would take control of the family's narcotics business in America. Tommy didn't want the plan to go forward (and threw Michael's business proposal in the fireplace), but it seems like Michael was willing to take any steps necessary to get back to America.

Michael and Gina also want Polly to come to America with them, which may explain why they killed her fiancé, Aberama.

Johnny Dogs

Johnny has always been incredibly loyal to Tommy and the Shelby family, but he's been under suspicion ever since Aberama's son Bonnie was killed by the Billy Boys, as Johnny was the only one who knew where they were camped.

Polly Gray

While we can't really see Polly going against her family in such a way, she had been showing doubts in Tommy's plans and delusions of grandeur, and she was tired of being in the middle of the spat between Michael and Tommy.

Additionally, a user on Reddit pointed out a very key detail about a cigarette left during the scene:

Right before the plan was discussed when they all barged into the bar, there is a cigarette butt that was just put out in a hurry. That specific cigarette was only smoked by Polly. However, when she left the bar after the meeting was over, she put it out, and no smoke was coming out of it. During the scene when they discuss the plan at the meeting, there are times where someone's vision is all blurry looking at the others in the meeting. It starts even before they come back into the bar.

Another Redditor also mentioned that right before Polly's resignation from the Shelby Company, she had an interesting conversation with Tommy. "Didn't Polly and Tommy's conversation mention a person (which I think it's Michael) who betrayed him, about choosing sides and stuff, and she asks 'what about me?'" they wrote.

Unfortunately, we won't know who exactly the mole was until the sixth season of Peaky Blinders premieres in late 2020 or early 2021, but it sure is fun to speculate.