FILM producer and former Bolton School pupil Andy Paterson has told of the challenges bringing a movie based on a best-selling memoir to the big screen.

Mr Paterson co-wrote The Railway Man, which stars Colin Firth and Nicole Kidman, and tells the true story of Eric Lomax, a British prisoner of war forced to work on the Thai-Burma railway by the Japanese during World War Two.

The film, released in cinemas last month, sees him track down his captor years later in an attempt to find reconciliation. Mr Paterson, whose wife Olivia wrote the screenplay for Girl With A Pearl Earring, called the story — from Mr Lomax’s best-selling autobiography of the same name — “undoubtedly the best I've ever been told”.

He said: “The main difficulties were finding a way to write it for the screen and how to afford the scale of production it demanded.

“On the face of it, this is a dark drama with scenes of torture and brutality — potentially difficult for audiences.

“We had to create a page-turning script capable of persuading financiers and then audiences that they had to see the film.

“Films are really all about tension — putting the audience on the edge of their seats, desperately needing to know what's going to happen.

“One problem here was we knew they would already know the ending, or at least that it is a story of reconciliation.

“Another is that it's a story of a man who comes home from war unable to talk of his experiences. That’s a very difficult character trait to make work on screen.”

The film stars Colin Firth, who won an Oscar for his 2010 portrayal of King George VI in The King's Speech, as Eric Lomax, Nicole Kidman as Patti Lomax and Jeremy Irvine as young Eric Lomax.

Mr Paterson, who left Bolton School in 1977 and went to Oriel College, Oxford, said: “On the production side I discovered a wonderful Australian director and by setting it up as a UK/Australian co-production I was able to raise the money.

“It helped that Colin Firth was kind enough to win his Oscar just as I was putting that stage together.

“We then found ourselves making a massive film, shooting in Scotland, Queensland and excavating the actual Thai/Burma railway from the jungle to shoot our biggest scenes where they actually happened.”

The Railway Man is scheduled for DVD release on May 19.