John (John C. Reilly) has been in a serious funk. For the seven years since his then wife Jamie (Catherine Keener) divorced him, John's social life has been pretty much non-existent. Things change, however, when Jamie encourages John to come to a party she's throwing. There, John meets Molly (Marisa Tomei), a woman who he quickly believes could be the woman of his dreams. The only problem? Her 22 year old son Cyrus (Jonah Hill). Molly and Cyrus are very close, and John is finding it difficult to get between the two, as Cyrus is not willing to share his mother with anyone else. Can John figure out the unique relationship between Molly and Cyrus and find a way to make them both happy, and by extent find a happy life with Molly?