Steven Knight during an interview that there were many interesting characters that he regrets killing in Peaky Blinders. He still laments the killing of gypsy gangster Aberama Gold (played by Aiden Gillen). Aberama wanted to avenge his son’s death. He was stabbed by unknown enemies while he was waiting backstage and Tommy’s plan was foiled. After so many years of fighting Aberama’s life was about to have a happy ending. Had the plan worked, he would have avenged his son’s death.Aberama was about to marry Polly (Helen McCrory), so his sudden demise was even more painful for all fans.
Steven regrets that Aberama should not have been killed so abruptly. Steven said ‘I should have kept him alive, I could have just wounded him,’.
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There were other favorites as well that Steven regrets killing and Barney Thompson ( played by Cosmo Jarvis) is one of them. Barney Thomspon was a retired soldier from the great war. He became mentally disturbed after the war. He was pulled out of mental asylum by Tommy for a special mission. ‘There’s him playing Barney Thompson (Cosmo Jarvis) who’s just brilliant and I really wish I’d kept him alive now because he’s such a good actor,’ he added.
“The other one is Tom Vaughan-Lawlor who played Malachi Byrne and it’s quite a small part but he just took it over and he was brilliant . . . but sometimes you have to do it because the story has to move on and there are obvious examples of characters who’ve gone.”Steven continued.
But nothing can be regretted more than the death of Major Chester Campbell ( played by Sam Neill). Major was a tough and determined villain to Cillian’s Tommy. Steven said, “A great one was Major Campbell and I thought we’d got to the end of that duel between Tommy and Campbell and I was writing episode six of that series and I thought ‘I can’t just send the script to Sam Neill’.”So, I phoned him up explained and he just said ‘I don’t want to die’ so I said ‘OK, I’ll think about it’ and did think about it and then a week later said ‘I think we’ve got to do this’ and he was fantastic about it.”

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Steven admits that killing a character is not a nice thing.”But it’s a funny position where you create these people and then you have to kill them and it’s not nice”, he added.
Although these characters may not be part of Peaky Blinders storyline now, but their absence will always be missed.