IMDB: http://www.imdb.com/title/tt0814335/
Trailer: http://www.youtube.com/watch?v=agcxkUGT7UY

Michael Harding (Penn Badgley) returns home from military school to find his mother Susan (Sela Ward), happily in love with a man known as David Harris (Dylan Walsh). He seems like the perfect father and husband to everyone - except Michael, who suspects that he isn't quite the man he seems to be.
9/10

This movie was awesome, watched it twice.