Greenberg is a fantastically complex part to play, but Stiller's performance is superbly nuanced, convincing and brave.

Greenberg is a great spectacle of toxic emotional stasis.

Greenberg is self-indulgent, boring and very cynical (and not in a good way). The anticlimactic ending doesn't sum up the movie but rather leaves you further frustrated at Greenberg for being a miserable, unlikeable person for no apparent reason.

This observant, clever, and at times painfully funny story showcases Stiller’s rarely tapped versatility as an actor, even if his character takes the entire length of the film to warm up to.