The film is adapted from the play of the same name written by Samuel D. Hunter. It tells the story of Charlie (Brendan Fraser), a 272-kilogram English teacher who lives in seclusion in a shabby apartment in rural Idaho, stubbornly and determinedly eating himself to death. Charlie abandoned his family in middle age for his same-sex lover, but after his lover's death, he overate because of grief and guilt, and tried to repair his relationship with his 17-year-old daughter Allie (Sadie Sink). As Charlie gets closer and closer to his inevitable fate, his friends Liz (Hong Zhou), a cynical atheist nurse, and Elder Thomas (Ty Simpkins), a young missionary, try to find the will to be saved in Charlie, both physically and spiritually. However, only Allie, Charlie's estranged daughter, can make him see a future beyond his current desperate state. Although Allie is sarcastic, hateful, and full of thorns, Charlie can find a last chance of redemption in her, and maybe even a glimmer of hope.