Sheridan Smith to reunite with Cilla writer Jeff Pope for new drama The Barking Murders

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Merchant (best known for comedies The Office and Extras) will play Stephen Port, a convicted serial rapist and killer who was sentenced to life imprisonment in 2016 for the 2014-15 murders of four young men, whose bodies had been found near Port's home in Barking, east London.

Smith – who has recently been seen in Cleaning Up and was nominated for a Bafta for her role in Pope's Cilla – will star as Sarah Sak, the mother of victim Anthony Walgate, alongside Jaime Winstone who will play Donna Taylor, sister of victim Jack Taylor.

"I love playing real life characters – especially an inspirational woman like Sarah Sak but with it comes responsibility," says Smith. "Along with the other families, Sarah went through so much heartache and it would have been easy for her to just accept what she was being told by the police, but something inside made her keep fighting for her son.”

According to the BBC, the three-part drama will "go beneath the headlines to shed new light on this story by telling it from the point of view of the families of Stephen Port’s victims, focusing on their fight to uncover the truth about what had happened to their lost sons and brothers in the face of a now widely criticised police investigation."

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The series is another collaboration from writers Pope and Neil McKay, who previously worked together on true crime dramas The Moorside, about the disappearance of Shannon Matthews and starring Smith, and Appropriate Adult, which looked at the story of serial killer Fred West through the lens of social worker Janet Leach.

The Barking Murders will go into production in spring 2019.