The emotional hothouse of the English boarding school yet again provides compelling drama in this subtly devastating adaptation of Kazuo Ishiguro’s imaginative novel. Attachments formed during adolescence resonate through the young adult lives of yearning, sensitive Carey Mulligan, seemingly manipulative Keira Knightley and boyishly bumbling Andrew Garfield – feelings heightened by their shared, particularly circumscribed fate. Director Mark Romanek (One Hour Photo) carefully creates an atmosphere redolent of a postwar England now slipped out of reach, but there’s something unsettling about it, something you can’t quite put your finger on. All of which is delicately judged given that the key twist comes out of speculative sci-fi territory, yet the big ideas never overawe the humanity of the characters. Softy Garfield is barely recognisable from his turn in The Social Network, a maturing Mulligan confirms the promise of An Education, but the real surprise is Knightley, alternately sharp and affecting in a career-defining contribution. (Notes by Trevor Johnston).