Igby Goes Down starts bleak, gets more depressing as time goes on and yet still manages to end cheerily without seeming forced. The story of a teenage boy born who rebels against the values he is born into: that of the upper classes. While certain parts of the plot are extraneous, it builds a fantastic view of the protagonists world and his (lack of) ambition.
Featuring a fantastic cast (including Kieran Culkin, Bill Pullman, Susan Sarandon, and Ryan Phillippe, among others), great direction and a genuinely interesting script: I would highly recommend this film.