Known for her turns on ABC's Lost and the high school noir film Brick, de Ravin will play Pattinson's love interest in Remember Me, about a couple struggling to stay together despite individual family tragedies.
Director Allen Coulter will head up the project, who previously made Ben Affleck's Hollywoodland and directed several episodes of Sex and the City.
Reps for de Ravin declined to comment.
What do you think? I don't think she looks 19-20. Amanda Seyfried would be a wonderful Ally.