In sunny Arizona, elderly Lenny gets mad at his girlfriend's home health care aide and writes in feces on his bathroom wall.
Lenny's daughter Wendy works as a temp in New York City and is an aspiring playwright. Her married boyfriend Larry comes by and she lies that she's had an abnormal pap smear.
Wendy calls her brother Jon in Buffalo after hearing about their father's behavior. She is quite upset, but Jon, a drama professor, does not want to deal with it.
Lenny's girlfriend suddenly dies in the middle of a manicure, and Wendy and Jon meet in Arizona. They are surprised to learn that their father has been placed in a hospital on the advice of his girlfriend's children, who no longer want him living in her house, based on a non-marital legal agreement.
The siblings visit their father, who is quite angry they have taken two days to see him. A doctor explains to them that Lenny has dementia indicative of Parkinson's Disease.
Wendy and Jon go to a nightclub to discuss what to do about Lenny. He insists that they find a nursing home; she is reluctant but doesn't know what else to do.
Later that night at a hotel, Wendy overhears Jon in a phone call with his girlfriend Kasia, crying about their breakup.
Jon leaves early the next morning. Wendy goes to retrieve Lenny's items from the house, which is already being sold.
Back at the hotel, Wendy goes through her father's memorabilia. Jon calls from Buffalo to tell her that he's found a nursing home for Lenny.
Wendy picks up Lenny at the hospital, and then endeavors to get him on a plane. In flight, she helps him to the bathroom, but his pants fall down in the aisle.
Jon picks them up at the Buffalo airport and takes them to the nursing home, which is designated a "rehabilitation center" and looks like a hospital. After they leave Lenny in his new room, Wendy gets upset that he no longer knows where he is, and tells Jon she feels horrible.
Jon brings Wendy to his house, which is filled with his academic research. Jon reassures Wendy that they are taking better care of their father than he ever took care of them. That night, Wendy explores the literature and videos that Jon compiled on nursing homes.
Wendy and Jon go over paperwork with the home administrator, who already wants to know their plans for Lenny's funeral and burial.
The siblings take Lenny to a diner to discuss his health care directives. Lenny is confused because he thinks he's been staying in a hotel, but angrily tells them to "pull the plug" if needed.
Wendy is surprised to find Kasia at the house, who is returning to Poland the next day. He cries the next morning when Kasia makes him eggs for breakfast. Then he drives her to the airport.
While playing tennis with Wendy, Jon injures his neck. He later needs her to help him with traction support at home, which he has used before. Jon asks her to stay in Buffalo through Thanksgiving to help with Lenny, and they argue about who has more important work. Wendy announces that she has won a Guggenheim fellowship that will fund her playwriting, much to Jon's surprise. He suggests they spend the holidays together and write, since he has been trying to finish a book on Bertolt Brecht.
Wendy calls Larry back in New York, who is caring for her cat. She becomes dismayed and hangs up on him.
The siblings go to a workshop on eldercare at the nursing home. They later attend a screening of The Jazz Singer that Lenny has requested. He becomes convinced that he is the protagonist and gets angry for a moment. Jon reassures his father, but he and Wendy are embarrassed by the racism of the movie.
They take Lenny to a nicer nursing home for an interview, but he has trouble with basic questions. Afterward, Jon gets upset with Wendy for denying the impending death of their father.
Wendy visits Lenny at the home and brings him a lava lamp.
Larry comes to visit Wendy, bringing her cat. They drive around Buffalo, which Larry has never visited before, and go to Niagara Falls. They go to a hotel to have sex, but Wendy gets upset about their situation, claiming that he is going through a typical midlife crisis. He claims that she is the one with a problem.
Wendy angrily leaves Larry when he drops her off at the home, where she finds Jon watching television with Lenny. She gets upset when she finds that his special pillow has been taken by a woman patient, and she takes it back. When she tries to return it to Lenny, he does not know who she is.
Wendy goes outside and meets a male nurse named Jimmy, with whom she smokes. He invites her to his van to get out of the cold. She mentions that her mother is "out of the picture," and talks about her playwriting. Jimmy explains that her father's toes have not begun to curl, which is a sign of death within a few days (from air leaving the body), so he has some time yet to live.
Wendy goes back to Lenny's room and looks at his toes, which are not curled.
The siblings take Lenny out for Christmas shopping. Jon has discovered that Wendy did not receive the Guggenheim fellowship and she gets mad at him for investigating. On the drive back to the home, the two argue about who is more talented, while Lenny turns down his hearing aid and tunes them out.
Wendy confesses to Jon that she got money from FEMA due to losing work after 9/11. He laughs at her.
Back at the home, Lenny's toes begin to curl.
Not knowing this, Wendy goes to the home to get her cat, where she is impressed that Jimmy has read her play. After a moment, she lunges forward and kisses him. She immediately apologizes, and he explains that he has a girlfriend.
During a lecture on Brecht, Jon gets a call, and is visibly upset.
The siblings go to the home, where Lenny has taken a bad turn. They spend the night, and the next morning Wendy awakes, touches her father's hand, and realizes he has died. She wakes up Jon, cries, looks at Lenny, and says, "That's it."
They later gather his things from the home.
Wendy returns to New York. Larry drops by her apartment with flowers. He tells Wendy that he needs to euthanize his old dog because her hips and legs have gone bad. Wendy hugs him, then he leaves.
Six months later, Wendy meets Jon at a small theater, where she is mounting a play that re-enacts a scene of Lenny beating him as a child. He cries. On the way out, Jon tells her he is going to a conference in Poland to meet Kasia's "people."
Wendy goes for a jog. Behind her is Larry's dog, following along with the assistance of a wheeled device.