No details had been shared on how Aunt Polly would be written out of the BBC One drama, but viewers saw the character's exit storyline in heartbreaking scenes where the other cast were shown grieving her loss in a three-minute silence.
The series picked up on the cliffhanger from the end of series five when Tommy Shelby (Cillian Murphy) was pointing a gun at his own head, but the opening scene revealed that Arthur (Paul Anderson) had removed the bullets from his gun to prevent a tragedy.
But when Tommy returned home, he received a horrifying call from IRA member Captain Swing (Charlene McKenna) who told him that she was responsible for the assassination attempt on Oswald Mosley being foiled and that a car pulling up outside his house contained the bodies of Tommy's associates who had been killed in the clash.
Tommy made the grim discovery that the bodies delivered to his door were Aberama Gold (Aidan Gillen), Barney (Cosmo Jarvis) and Aunt Polly, with Captain Swing telling him she had killed Polly as a message to him that she had "changed the structure of his organisation" and that Polly's death was his own fault as he had failed to realise his own limitations.
In an emotional scene that paid tribute not only to the character of Aunt Polly within the show but also to the cast's beloved co-star McCrory, the Shelbys held a memorial to honour her Romany gypsy heritage by burning a carriage with her photos and painting inside.
During the scene, which contained a three-minute silence while the carriage burned, the camera panned to each member of the family who were in tears over their loss - while Polly's son Michael (Finn Cole) vowed vengeance on Tommy for his part in her death.
Sophie Rundle, who plays Ada Shelby, has said that she had to film her part separately because she was pregnant at the time but had been shown the rest of the cast in the scene first.
Ahead of the series launch, Murphy explained to Empire that McCrory had originally been due to film for the series but that the coronavirus pandemic had halted filming in March 2020, and she died of breast cancer a year later in April 2021.
He said: "What I always feel sad about is that we were about to shoot and then the pandemic happened and we had to stop. If we had shot then, Helen would've been in the show, and that makes me feel sad.
"It's a huge loss; it's hard to comprehend it. Because she was the matriarch of the whole thing. As the character, but just also as her personality. But she's still present in series six.
"Steve [Knight, show creator] has managed to keep her very, very present, which I think is a brilliant tribute to Steve and also to Helen. But we couldn't quite fathom it all as we were making it, you know?"
Peaky Blinders continues on Sundays at 9pm on BBC One.
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