Notes On A Scandal, Zo Heller

From the first day that the beguiling Sheba Hart joins the staff at St George's, history teacher Barbara Covett is convinced that she has found a kindred spirit. Barbara's loyalty to her new friend is passionate and unstinting and when Sheba is discovered to be having an illicit affair with one of her young pupils, Barbara quickly elects herself as Sheba's chief defender. But all is not as it first seems in this dark story and, as Sheba will soon discover, a friend can be just as treacherous as any lover.

Now a major motion picture starring Judi Dench, Cate Blanchett and Bill Nighy.