The Wire star takes on the role of Fred West in upcoming U.K. TV drama Appropriate Adult, which centres around the interviews West gave to cops after his arrest in 1994.
The actor admits his own wife was "revolted" when she discovered he'd agreed to take on the part - and West confesses he found some "common ground" with the serial killer while undertaking the role.
He tells The Sunday Times Magazine, "Everyone who came into contact with him (Fred West) thought he was a good guy. Salt of the earth. The police all liked him. He escaped detection for 25 years because he was likeable, and pitiable.
"(West's wife) Rose was not... This is very, very, very dangerous territory, but necessarily one has something in common. You have to find common ground and that common ground is the basic part of you."
Fred West was charged with murdering at least 11 girls and burying many of their remains at his home in Gloucester, England in the 1970s. He committed suicide while awaiting trial in 1995. His wife Rose West is currently serving a life sentence for 10 of the murders.