LONDON — Nicole Kidman has been cast as Colin Firth’s wife in ”The Railway Man,” replacing Rachel Weisz in the role.

Weisz was forced to drop out of the project because she’s required to do additional shooting on ”The Bourne Legacy” and ”Oz: The Great and Powerful.”

The Railway Man,” directed by Jonathan Teplitzy, is in pre-production to start shooting in April. A U.K.-Australian co-production backed by Lionsgate Intl., it’s based on Eric Lomax’s autobiography about his horrific experiences as a Japanese prisoner in World War II, and his remarkable reconciliation with one of his captors 30 years later.

Lomax’s wife Patti, who will be played by Kidman, took a key role in helping him to face up the longstanding psychological damage caused by his wartime horrors, and in bringing him back together with one of the Japanese officers who had participated in his torture.

Jeremy Irvine (”War Horse”) plays the younger Lomax in the WWII scenes.

Producer Andy Paterson co-wrote the adaptation with Frank Cottrell Boyce.

”The Railway Man” will shoot in Scotland with Firth and Kidman, before moving to Australia’s Gold Coast for the WWII section.