12 Years A Slave
Chiwetel Ejiofor is favourite to win the 2014 Best Actor prize for 12 Years a SlaveeOne

John Ridley has revealed that he agreed to write the script for Steve McQueen slave drama 12 Years a Slave free of charge.

Nominated for nine Oscars, including an Adapted Screenplay nod for Ridley, the film has been both a critical and commercial success having topped the UK box office.

"There was no development money whatsoever for this project," he told Press Association. "So I said I'd take it on as a spec project, which means I'll write it for free."

"The upside is I get to own that manuscript; the downside is, for what? This was not Transformers, where you can go to a studio, where they say, 'Great. Let's put some big stars in and go.'

"It was either going to be a script that wowed people and show how powerful that memoir and that story was, and how pertinent it is. That was the difficulty of it. That was something that came to me in a partnership but ultimately it was a choice of four year's work without taking a penny."

Ridley who adapted his script from Solomon Northrup's memoirs of the same name, was eventually paid for his work – but only after finishing it and as production was about to begin.

"In the end, it worked out brilliantly," he added.

As well as its screenplay nomination, 12 Years a Slave finds itself nominated for Best Picture, Best Director for McQueen, Best Actor for Chiwetel Ejiofor as Northrup, Best Supporting Actress for newcomer Lupita Nyong'o and Best Supporting Actor for Michael Fassbender.

Ridley admitted disbelief over how many Oscar nominations the film has received. "It's been odd. I've had a disconnect. It feels like the announcement happened about two or three years ago, when I know it was just days ago."

"I am very thankful of the recognition, of the acknowledgement. To make a film that's good is hard, to make a film that's wonderful is difficult. To make a film that is probably one of the best years for film in America, around the world, and have people acknowledge it, it has not yet sunk in."