The first image has been released of Stephen Merchant as Stephen Port, who received a life sentence with a whole-life order in November 2016.
Four Lives tells the story of the four men killed by Port: Anthony Walgate, Gabriel Kovari, Daniel Whitworth and Jack Taylor, and their families and friends who worked tirelessly to find out what happened to them.
It will air over three consecutive nights from 9pm on Monday 3 January on BBC One, with all episodes on BBC iPlayer from the same time
From Jeff Pope and Neil McKay, the award-winning team behind The Moorside and Appropriate Adult, the new factual drama will go beneath the headlines to shed new light on this story by telling it from the point of view of the families and friends of the four young men - Anthony Walgate, Gabriel Kovari, Daniel Whitworth and Jack Taylor - who were murdered by Stephen Port. Four Lives focuses on the fight to uncover the truth about what had happened to their lost sons, brothers and loved ones in the face of a now widely condemned police investigation.
The three-part series will begin at 9pm on Monday 3 January on BBC One, continuing at the same time on Tuesday 4 January and Wednesday 5 January. All three episodes will be available on BBC iPlayer from 9pm on Monday 3 January.
Written by Neil McKay, Four Lives (3x60’) is directed by David Blair, produced by Serena Cullen and executive produced by Jeff Pope for ITV Studios, Neil McKay and Lucy Richer for the BBC.
The drama was commissioned by Piers Wenger, Director of BBC Drama, and Charlotte Moore, BBC Chief Content Officer. It is a co-production with BritBox North America, where it will premiere in the US and Canada, and is distributed internationally by ITV Studios.
The cast also includes Rufus Jones (Stan & Ollie), Stephanie Hyam (Bodyguard), Leanne Best (Line Of Duty), Samuel Barnett (Dirk Gently's Holistic Detective Agency) and Robert Emms (Chernobyl).
Four Lives was initially announced with the working title of The Barking Murders.
Jeff Pope and Neil McKay previously worked together on The Moorside, which told the story of the community impacted by the disappearance of Shannon Matthews; and Appropriate Adult, which looked at the story of serial killer Fred West from the point of view of trainee social worker Janet Leach. They have a reputation for factual drama based on detailed research that focuses not on the crime itself, but those affected by the events, whose perspective gives a fresh eye on these important news stories.