Colin Firth and Rachel Weisz are amongst the big names to sign up for Boer War political thriller The Colossus.

Ian McKellen and Susan Sarandon will also star in the film, based on the novel Manly Pursuits by Ann Harries.

The film, currently in pre-production, has a $15 million budget and is about the arch-colonist Cecil Rhodes' belief that he can only recover his health if he hears the sound of English song birds outside his window in Cape Town.