Sheridan Smith pictured in BBC drama about serial killer Stephen Port

Sheridan Smith plays Sarah Sak in the three-part BBC One drama

The BBC has released the first picture of Sheridan Smith as she appears in a new factual drama about the crimes of serial killer Stephen Port.

Smith plays Sarah Sak, the mother of one of the four young men Port poisoned with lethal doses of a date rape drug between June 2014 and September 2015.

The drama, whose working title is The Barking Murders, will air this year.

Extras star Stephen Merchant will play Port, who was sentenced to a full life jail term in November 2016.

Writers Neil McKay and Jeff Pope said they were "so grateful" the co-creator of The Office had "agreed to take on such a difficult and challenging role".

Stephen Merchant (left) will play Stephen Port (right)

Samuel Barnett, Rufus Jones and Jaime Winstone will also appear in the three-part series, which will focus on the victims' families.

Pope and McKay previously worked with Smith on The Moorside, a 2017 drama about the hoax kidnapping of nine-year-old Shannon Matthews.

The release of the picture of Smith in her latest role coincides with reports that she is currently in talks to play Samantha Fox in another TV drama.

"I would love for Sheridan to just say yes," the model and pop star told the Daily Star. "She would be perfect."