The Wire star plays the iconic activist and politician in Mandela: Long Walk To Freedom, but did not take his representative seriously when he first mentioned the role.
Elba assumed Mandela would be played Denzel Washington, who had been considering the script, and was stunned when producers offered him the part instead.
He tells the London Evening Standard, "My agent in South Africa said, 'Do you want to play Nelson Mandela?' I was like 'Roger, shut up, I haven't got time man, call me later - click. For a long time Denzel Washington had this script and was working with this team. Everyone in the industry knew Denzel would play Mandela one day. When they called me I couldn't believe it. I am not going to lie, I was scared.
"It was tough to walk into a room with extras who had never seen me before. How do you get these people to look me in the eye when I was speaking and believe me as Mandela."