What is childhood, if not the grim fairy tales and horrible lies that adults tell the young? That's the curriculum in the elite English school Hailsham, a kind of Hogwarts for gifted children of a different kind, who are pampered and imprisoned until they grow older and realize their brief destiny. Carey Mulligan, Andrew Garfield and Keira Knightley are splendid as the docile, haunted young adults in this science-fiction tale of love and submission, adapted by Alex Garland from a Kazuo Ishiguro novel. Director Mark Romanek cradles his actors in an internal landscape of delicate, worn beauty. A challenge in its subtlety — too muted and fatalistic, perhaps, to please most audiences — the film says that whether we live to be 30 or 90, we all have a death sentence hanging over us. Never Let Me Go is a whispered plea to live and love well, so that long before our time is up, we will truly have reached completion. That way, we can live forever.