In the show, the Game of Thrones actor plays Mark, a convict who befriends prison officer Eric, played by Stephen. The official synopsis reads: "Mark Cobden is consumed by guilt after accidentally killing an innocent man.
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"Accepting his four-year sentence and separated from his family, he meets Eric McNally, a caring prison officer doing his best to protect those in his charge. However when one of the most dangerous inmates identifies his weakness, Eric faces an impossible choice; between his principles and his family."
It concludes: "A visceral, emotional and high-stakes portrayal of life in a British prison; A story of guilt and forgiveness, punishment and penitence, both Eric and Mark are trapped by their pasts and unsure of their futures. Will they find the strength to move forward?"
Get the first look from BBC's Time
The series is currently filming in Liverpool and has yet to have an airdate, so we can't wait to find out more!
Stephen revealed that he recently lost out on his role on Peaky Blinders due to the lockdown. Speaking on the podcast Pound for Pound about how his role has been put on hold back in April, he explained: "I was supposed to be starting Peaky Blinders but that has been put on hold indefinitely. My agent spent a lot of time putting that together."
Stephen opened up about his role that has been postponed
The showrunner Steven Knight previously opened up about Stephen's role in the upcoming series while a guest on the Obsessed with... Peaky Blinders podcast, explaining: "The amount of people who have come to us wanting to be in it is quite astonishing, and really good people.
"So what I've tried to avoid before is turning it into a 'spot the celebrity' – you know, because I think it's quite distracting sometimes."
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