Billy Crudup gives a commanding performance as a neurotic, misanthropic author of children’s books; Tom Wilkinson, pitch-perfect as always, is his father figure and only real friend, an illustrator whose own disdain for humanity has receded with the years. Their book Marty the Beaver becomes an improbable best seller, but for the follow-up Crudup is assigned a new illustrator (Mandy Moore) and seems ill equipped to work with anyone but his old partner. Actor Justin Theroux makes an impressive directorial debut, aided by David Bromberg’s mordantly funny dialogue. With Bob Balaban and Dianne Wiest. R, 111 min.