Sheridan Smith has confessed how grown up she felt to be cast in new TV drama Mrs Biggs.
The 31-year-old actress, is leaving behind the tracksuits and peroxide of her roles in Benidorm and Two Pints Of Lager And A Packet Of Crisps to play Charmian Biggs, wife of train robber Ronnie, in the first drama series to focus on her side of the story.
Sheridan said: "It's really grown up for me. I don't usually get to play sophisticated women, I usually play the scruffs, the chavs and the slappers.
"Although I've loved the roles I've played, it's been so nice they've given me this opportunity, and it's scary, you feel a bit out your comfort zone, but I'm loving every minute."
Charmian urged Ronnie to turn his back on a life of petty crime but, just as they were trying to stump up enough money to buy a house, he was offered a role in one of the most famous British crimes of all time - the Great Train Robbery of August 1963. Biggs and the rest of the gang stole £2.6 million from a mail train travelling from Glasgow to London, and the train's driver, who was beaten during the robbery, never fully recovered from his injuries.
Sheridan said of Charmian: "She's an incredible woman. She remembers so much, even down to what she was wearing when certain things happened. She'll say, 'I didn't have flats then, I had heels', for example."
Though Sheridan describes Ronnie, who is now 83 and suffering from ill health, as a "loveable rogue", she's also quick to point out that the drama doesn't glamorise his crimes either.
She said: "It just tells the female side of the story, and I think it is so important to know what she went through."
:: Mrs Biggs continues on ITV1 on Wednesdays.