The Hollywood Reporter brings us the news that McAvoy, best known lately as Tumnus in The Chronicles of Narnia, will star as Robbie Turner, a childhood friend of Cecilia Tallis (Knightley) and a man accused of rape by a 16-year old.

The story begins on one fateful afternoon in which Robbie and Cecilia along with Cecilia's younger sister Briony will find their lives change. Robbie and Cecilia will have crossed a boundary they had never before dared to approach and will have become victims of the younger girl's scheming imagination. And Briony will have committed a dreadful crime, the guilt for which will color her entire life.

The part of Briony has not yet been cast.