Des star Daniel Mays says that filming such a chilling drama can come with a cost.
The actor, who plays DCI Peter Jay, admitted that it was "really tough" to film because of the twisted, psychological nature of the content.
The three-part series is based around the real-life murderer Dennis Nilsen and his appalling catalogue of gruesome crimes during the 1980s.
DCI Jay leads up the investigation, with Daniel even taking time to speak with his family to get a broader, more comprehensive understanding for the character.
Now he's told that filming the drama took its toll.
Sitting down for a chat with NME, Daniel told that he'd woken his wife after a deeply sinister nightmare.
"When you're preparing for a role like this, you have to delve into what happened and it was really, really tough," he told.
"I woke my wife up screaming because I was having a nightmare that I was in an attic with Dennis Nilsen."
Daniel added: "The content was really toying with my mind, but that was a great thing to experience because when you look at it and policing at that time and what Peter and his team went through, they weren't privy to any form of counselling or anything like that.
"Their counselling was going down the pub and drinking copious amounts of alcohol, not opening up to their wives.
"Talking about your feelings wasn't common for men of the 1980s, so the drama is also an amazing investigation into what it was like to police at that time too."
Daniel went on to say that shooting the drama felt "eerie" from the offset - particularly because of the frightening performance of David Tennant, who plays the eponymous murderer.
Nilsen was a Scottish murderer who killed boys and young men he met on the streets of Soho between 1978 and 1983.
Dubbed the Muswell Hill Murderer, he also mutilated and dissected their corpses, before flushing them down the toilet or burning them in bonfires.
His killing spree ended when the smell of rotting corpses in his home was picked up on by neighbours, with body parts blocking local plumbing.
