The movie opens as Pat Solatano, played by Bradley Cooper, is participating in a group therapy exercise within a mental institution. Another patient named Danny, who is played by Chris Tucker, begins to explain his last haircut as Pat begins to talk about his outlook on life: Excelsior. Pat's mother arrives at the mental institution and explains that the court has allowed her to come get her son as he has served his court-mandated 8 months. Pat's doctor disagrees that he is ready but nonetheless, Pat and his mother leave.
As they are driving through the parking lot, Pat asks his mother if she can give Danny a ride, who has also been released that day. As they are driving, Danny explains the legal process through which he was able to leave early. As he is explaining, Pat's mother receives a phone call informing her that Danny was not released and needs to return immediately. Pat's mother gets upset with Pat and begins to think she might have made a mistake taking him out so soon. Danny takes the blame and sticks up for Pat saying that he didn't know about Danny's plan to escape and that he will go back voluntarily. Pat's mother agrees, and it quickly cuts to just them two in the car after they have apparently dropped Danny off and returned back on their way home.
Pat is greeted at home by his father, played by Robert De Niro, and an older gentleman. Pat's father is surprised that his mother has brought him home as she did not tell him. She explains that the judge allowed him to come home into their care, and Pat's father asks if the doctor agreed. Pat explained that the judge let him and everything will be okay. Pat's father gives him a hug and asks if he is still wearing a necklace that he also wears. Pat's father explains that he lost his job, however, he is going to open a restaurant, but in order to earn enough money, he is going to be a book-keeper for sports bets. We then see him watching an Eagles game, but insisting on having his three remote controls in a certain order as he is squeezing a handkerchief in his hand. It is apparent through his actions and Pat's snide remark that his father has OCD.
Later that night, we find Pat just finishing up an Ernest Hemingway novel in his room in the attic. He is visibly frustrated and then throws the book out of the window, breaking the pane of glass. He storms into his parent's room where they are sleeping and explains his frustration at Ernest Hemingway. He explains that all throughout the novel, he was rooting for the main character to survive the war and end up with his true love which doesn't happen at the very end. As he is leaving their room, his parents ask him to apologize, and Pat explains that it's Hemingway's fault and not his, to which his father asks him to have Hemingway apologize for waking them up at 4 am.
It's the next day, and Pat is wearing a sweat suit with a garbage bag over his torso like a poncho. He is about to start running down the street when his dad catches him and tells him that he needs to fix the window before he starts to run. Then his mom finds him and says he actually needs to go to therapy before all else. Pat protests, but then his mother explains that it is a requirement from the judge as one of the conditions of his release.
Pat enters the waiting room to check in for his appointment with a therapist. There is a song playing on the office radio, and he becomes upset with the receptionist and accuses her of purposely playing that song to anger him. She looks bewildered as he begins to rip out a shelf of magazines looking for the speaker. His therapist comes out of his office as the other patients in the waiting room stare in astonishment. Pat apologizes and starts picking up the magazines.
As Pat sits down, his therapist explains that he did play that song on purpose to test if it was still a trigger for Pat's anger. As it obviously is still a trigger, he explains he needs to come up with a strategy for his anger. Pat explains that his strategy is excelsior, which means finding the silver lining in all situations. He then explains that he has lost weight over the past 8 months and is going to get better so he can reconcile with his wife, Nikki.
Later that day, Pat is running around the neighborhood when he runs into a friend, Ronnie, played by John Ortiz, as he is arriving home. Ronnie apologizes for not coming to see him in the hospital as he has a new baby and was too busy with work but invites him over for dinner the next evening. Pat tries to decline stating that Ronnie's wife hates him at which point his wife, played by Julia Stiles, yells through the window to see if Ronnie had invited him yet. Ronnie explains that he is asking him at that very moment and Pat agrees to go.
As he continues to run, he passes a school and he sees an older teacher walking inside. He catches up with her and asks if she has seen Nikki. She is visibly afraid of Pat, however, he continues to cheerfully talk with her. He explains that he is better and ready to start working at his old job. She tells him that she cannot tell him if Nikki still works there but that a certain history teacher does. He is upset at this comment.
Later that evening at his parent's house, a police officer, played by Dash Mihok, comes to the door and explains that Pat violated his restraining order by visiting the school and that he has been assigned to his case.
During his therapy session the next day, Pat tells his therapist that he has been invited over for dinner and is unsure if he should wear a Gap shirt his mother bought him or an Eagles jersey his brother just sent him. His therapist asks which player the jersey is for and when Pat responds, his therapist tells him that he can't go wrong with that player.
Pat wears the jersey to dinner and is talking with Ronnie before dinner starts. Ronnie explains that he is happy but sometimes feels as though he's suffocating in his life. Pat tells him that's not normal when Tiffany, Ronnie's wife's sister, played by Jennifer Lawrence, arrives. Ronnie instructs Pat not to bring up the death of Tiffany's husband. As Pat greets Tiffany, he tells her that she looks good but adds that he is not flirting with her. He then immediately asks how her husband died. Ronnie and his wife give them both a tour of their house and show them an electrical fireplace and ipod docking stations they've recently had installed in every room. They sit down to dinner, and Pat and Tiffany begin to discuss the different kinds of medications they have both taken. Ronnie's wife complains about Pat's jersey and compliments Tiffany on her dance lessons she's been taking. Tiffany decides that she is ready to leave dinner before she has even finished her salad and asks Pat to walk her home. Although Pat remarks that she is acting inappropriately, he agrees to walk her home.
They arrive at her house, which is a guest house located behind her parent's house that she moved into after her husband's death. She tells Pat that she hates his football jersey, but he can have sex with her if he wants as long as they turn the lights off. Pat is taken aback by her statement and holds up his ring finger to show that he is married. Tiffany also holds up her ring finger and says that she is, as well. Pat makes an offensive remark about her husband and she hugs him as she starts to cry. Then she slaps him and leaves.
Pat goes home and starts to look for his wedding video which he cannot find. He becomes more and more frustrated and wakes up his mother to help. They go into the attic, and Pat becomes more erratic and starts shouting. His mother attempts to hug him, but he accidentally elbows her and his father comes in to see what all the yelling is for. Then the same police officer from before arrives and advises them that their neighbors had called as they were concerned about all of the yelling.
The next day, Pat is running and again wearing his sweat suit and garbage bag combination. He groans as he realizes that he is running past Tiffany's house. He picks up his pace, but then suddenly Tiffany is running behind him. He asks why she is following him, but she explains that he is the one running past her house. They continue to run with Pat in front and Tiffany chasing him.
Tiffany shows up twice more suddenly while he is running. Once she is wearing normal running clothes and the second she is wearing jeans and a jacket. Pat complains about Tiffany showing up around him, and his therapist tells him that perhaps she is a friend in need and if his wife sees him helping a friend, that might help him look better. After they continue to run, they end up in front of a diner where Pat asks Tiffany if she wants to have dinner with him that night.
They meet later at the diner where Pat orders cereal and Tiffany orders tea. Pat explains that since he ordered cereal, it is clear they are not on a date. Tiffany reveals that she recently lost her job because she slept with 11 people in her office. Pat asks for details and finds out she also slept with a woman which turns him on. Pat reveals that he came home one afternoon and heard his wedding song on the radio while his wife was in the shower. He found her in the shower with the history teacher at their school. That is when he blacked out somewhat and almost beat the history teacher to death. Tiffany agrees to give a letter to Nikki from Pat. Pat then implies that he is not as crazy as Tiffany when she gets upset and brushes everything from their table onto the floor and says that it's okay because she's crazy as Pat says. The diner cheers as she walks away as they have assumed Pat was in the wrong. Pat catches up to her outside of a movie theater where he grabs her and attempts to stop her from leaving. She yells that he is harassing her and a group of boys come to stop him. His wedding song is playing in the background, and he starts to get angry. Tiffany realizes this and tells a nearby police officer that the young boys enticed him.
Tiffany meets Pat and tells him that she won't give Nikki the letter unless she gets something in return--if Pat agrees to dance with her in a local amateur competition. He agrees, and they begin to practice dancing in her apartment studio.
At one of the scheduled rehearsal times, Pat shows up at TIffany's studio, however she is not there. He goes to her parent's house where her mother tells her that she is not home and to leave her alone as she has assumed he is one of the men from Tiffany's work that is just looking for a good time. Another man shows up at the door at the same time also looking for Tiffany saying that she has been texting him, and they are dating. Pat tells the man to leave and explains that she is not that kind of girl and deserves respect. The camera then reveals that Tiffany is on the other side of the wall and has heard the entire conversation.
Danny comes to Pat's parents' house, again stating he was released. He watches Pat and Tiffany rehearse and helps Pat put 'soul' into his moves. Pat's father has Danny hold the remotes in the position he believes will help the Eagles win the football game. The police arrive and again it is revealed that Danny left without approval. Pat's father is upset as he believes the Eagles will not win because Danny had to stop holding the remotes.
Tiffany gives Pat a letter from Nikki, which tells him to continue doing well, and as she's reading the signs it seems as though he is improving. She urges him to do something to prove he has changed before she will think about reconciling.
Pat's brother comes home for the weekend, and they attend an Eagle's game together. He sees his therapist at the tailgating party and a group of men start to harass and fight with his therapist because of his Indian descent. Pat tries not to get involved but can't handle resisting when they start to attack his brother. The police break up the fight, and they miss the game. Pat also misses his rehearsal with Tiffany which was an important one due to the fact they were going to practice the big lift.
Tiffany arrives at Pat's parents' house to confront Pat about blowing her off. Pat's father insists that she is the reason the Eagles have been losing. She then recites all of the days she spent with Pat and the scores of the games, which they all won. Tiffany also says that as she's reading the signs that she thinks Pat's father shouldn't have sent Pat to the game because the New York state motto is Excelsior and they were playing the Giants at the time. Pat's father admits he needs to rethink his decision and changes his mind about Tiffany. Pat's father had made an all or nothing bet with his bookie friend and lost that day. They all then make another bet to go double or nothing with a parlay, which means that Pat and Tiffany have to score at least 5 points at the dance competition in order for Pat's father to win the bet. As Pat and Tiffany are leaving, he realizes that TIffany used the same words that are in the letter from Nikki, 'as I'm reading the signs.' Pat then realizes that TIffany wrote the letter. Tiffany stayed inside to talk with Pat's parents where the mother reveals that she had been calling Tiffany to tell her where Pat was running so she could catch him. They all three then decide they need to tell him that Nikki will be at the dance competition in order to convince him to go because he doesn't want the pressure from his dad's bet on his shoulders.
Pat writes a letter later that night in his room.
Tiffany tries to tie several ties unsuccessfully on Pat as he stands in his suit watching her. They make it to the dance competition along with Pat's parents, brother, and the older bookie. Tiffany is taken by surprise when she sees that Nikki actually did show up for the competition. She confronts her sister because she is angry as she has fallen in love with Pat. Tiffany's sister explained that Nikki and Pat's marriage was more important, and they deserved a chance to get it back. Tiffany is distraught and goes to the bar where she orders a drink and begins to flirt with a man at the bar.
Pat finds her at the bar just moments before they are to be on the dance floor. They complete a medley of different dance types. During the big lift, Pat doesn't lift Tiffany high enough, and she just sits on his face and shoulders. They finish the routine in an almost-kiss. They wait for their scores and end up getting a 5.0. The other dancers tell them that they might have better luck next time but Tiffany, Pat, and the whole family start to cheer very loudly which confuses the rest of the audience as a 5.0 is not a very good score, however, they have unknowingly just won the bet Pat's father had made as the Eagles had also just won their game.
Tiffany and Pat hug, but then he sees Nikki and breaks to go talk to her. Tiffany sees this and runs out of the building. Pat finishes talking to Nikki and finds his father. He tells him that Tiffany left because she saw him with Nikki. His father also tells him that he is sure that Tiffany loves him, and he was never sure if Nikki ever did and advises him to take advantage of this moment and do the right thing.
Pat runs out of the building and catches up with Tiffany. He gives her the letter he has had for a week, and it reveals that he loves her. She tells him that she can't believe that he let her lie to him for a week. They kiss and embrace.
The next scene happens after a short period of time has elapsed. They are watching an Eagles game at Pat's parents house, and the movie ends as Tiffany sits on Pat's lap and they kiss and embrace.
You can send in your spoiler to other movies by going here.