Chiwetel Ejiofor 'hesitant' over 12 Years a Slave role
12 Years a Slave star Chiwetel Ejiofor has said he was initially hesitant about taking the lead role in Steve McQueen's Oscar-tipped film.
The 36-year-old told the BBC he needed "a moment to work out" if he wanted to take on the part.
"When I read the script, I thought it was an extraordinary story but I did feel the weight and the responsibility of it," he said.
"I didn't want to be the guy that messed it up."
Ejiofor is hotly tipped to receive a best actor Oscar nomination for his performance.
The film tells the true story of Solomon Northup, an African American who was born free but was kidnapped and sold into slavery in 1841.
"I hadn't seen a story from inside the slave experience as a film and I'd been accustomed to the fact I'd probably never see it," Ejiofor told the BBC's arts editor Will Gompertz.
"So to be handed that kind of opportunity and the responsibility of telling [Northup's] story - I just questioned myself and was stuck for a moment with the questions of whether I could do that.
"Is there somebody else who has more access to this than you do? Can you get to all the places you need to get to in order to play this role and satisfy it?
"Is it going to be something that looking back on it you're proud of, or embarrassed, or worried by? My head was filled with all those questions."
McQueen's film is an adaptation of Northup's memoir, in which he described the 12 years he worked on plantations in Louisiana, before his eventual release.
Ejiofor said filming on the plantations felt like "dancing with ghosts... present right in the soil.
"There are some places that have a rich investment in what happened there - there are some turned into museums," he said.
"Then there's other places that seem very removed, almost as if it never happened.
The actor, who has been nominated for a Golden Globe for his role, played down suggestions of Oscar success in March, but said he was "really excited about the prospect".
12 Years a Slave goes on general release in the UK on 10 January.