The 'Peaky Blinders' cast smokes herbal tobacco throughout filming the BBC series, according to Helen McCrory.
The 50-year-old actress - who plays Polly Gray in the hit show - has revealed that the cast make their way through around 5,000 cigarettes during each series of the programme.
She told the Sunday Mirror newspaper: "They use herbal tobacco which has no nicotine and tastes horrible. They're the same type they smoke in theatre productions.
"I used to go to plays for years and wonder why they had a [cannabis joint] on the go during a play and how they could remember their lines.
"It smells, to a layman like me, like someone is smoking cannabis. It's just a bit funny and not like tobacco."
Meanwhile, Helen recently confessed she couldn't watch the "disgustingly violent" opening episode of the new series of 'Peaky Blinders'.
The actress warned fans about "disturbing" scenes in the fifth season, but she insisted the portrayal of such savagery "should be horrifying".
She said: "It is very violent and it's really horrible and you should look away.
"I've only seen episode one, and there's a whole bit ... We saw the screening in Birmingham, for fans who managed to get lottery tickets.
"I look away from the screen. I as Helen can't watch it. I think it's disgusting, gratuitous violence. It is ... no, not gratuitous - disgustingly violent.
"But it is. And it should be. I think it's much more disturbing than somebody slashes somebody's face or somebody shoots somebody and it's all just the end of it."
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