The Rosie Project

Though he is very upset, Don does not shut down. Gene and Claudia follow him home and try to get him to let them come in. He refuses. He returns a happy birthday call from his family and corrects their impression that he is gay, by telling them that the redheaded woman in the picture with him on Facebook is the woman he was dating.

Don recounts all he has learned about himself during the Rosie Project and decides that, realistically, he can have a relationship with a woman, even if he cannot love Rosie the way she wants to be loved. He knows that he must do more work on himself, and thanks to the success of the Don Project, he knows that he has the tools to keep growing and improving. 

When Don wakes up, he has further insights. Without consciously realizing it, he has resolved an issue that was bothering him. Rosie’s insinuation that he lacks empathy and the ability to love isn’t true. He does have an ability to empathize, but the situation has to involve someone he loves or cares about, not a fictional movie character. He recounts many instances of his empathy, including occasions in his relationships with Daphne, Claudia, and Rosie herself. Even a somewhat compromised ability to empathize does not mean that Don cannot love, because he knows he loves Rosie.

He runs back to find his coat, because he left his cell phone in the pocket. A homeless man has taken his jacket from the trash can, and Don carefully removes his cellphone and an envelope from the pocket of the coat. A couple watches him apparently robbing a homeless man and calls the police.

Don rides his bike to campus, one step ahead of the police. In his office, he finds that his Father Project file has been ransacked by Rosie, who has left him a note, apologizing. Afraid that she will confront Gene without DNA proof of paternity, he rushes to locate Gene and head Rosie off. He finds everyone at the University Club—Gene and the Dean at one table, Rosie and Claudia at another.

Don rushes up to Rosie and announces that he knows he loves her, because he loves her despite her flaws and still wants to marry her. Rosie presents the ring from the previous night’s proposal. She puts it on her finger and agrees to marry him. Don kisses Rosie to the applause of the entire dining room. The police arrive to question Don about what he took from the homeless man; he shows them that he has three tickets to Disneyland in his pocket.

Don, Phil, and Rosie go to Disneyland. Don and Rosie marry and move to New York City, where Don works in the Genetics Department at Columbia University and Rosie attends medical school. They decided to move to make it easier for Don to maintain all of the positive changes that he has made. Rosie and Don work together three nights a week in a cocktail bar for extra income. They are trying to have a baby.

Don takes the remaining DNA samples from the Father Project, plus one additional sample taken from Phil, and tests them. Don texts Rosie so that she can be there to see the results. Phil is her real father.

Don blames Gene for the entire mix-up. As the professor of the genetics class the medical students took at the time, Gene vastly simplified his explanation of eye color inheritance. Rosie’s mother had no way to know that her education was not complete and that she based the confession of her affair to Phil on incorrect information, believing it was impossible for two blue-eyed people to have a child with brown eyes. Don marvels that without Gene’s mistake, he would never have met and married Rosie.