New Zealand author GAVIN BISHOP is claiming breach of copyright after insisting the makers of hit movie MR AND MRS SMITH stole his idea. The children's writer says the Brad Pitt film was "too close to be accidental" to a children's book he wrote in 1997 entitled THE SECRET LIVES OF MR AND MRS SMITH. The couple, who appear in the movie as assassins, are featured in the book as spies - the only significant difference is that the pair are unaware of their respective double lives. He says, "The fact that my book was published in the United States and was available to thousands of school children - it doesn't seem too far-fetched to think the Hollywood scriptwriter of this film may have come across my book." Bishop cannot afford to sue, but is keen for a lawyer to take up the case. Movie studio 20th Century Fox is investigating the claims.