The Rosie Effect (2014) is an adult romantic comedy and sequel to the bestselling The Rosie Project (2013), written by Australian author Graeme Simsion. In The Rosie Project, genetics professor Don Tillman’s efforts to identify an ideal wife lead him to fall in love with Rosie Jarman, a spirited PhD student who defies his requirements. The Rosie Effect features Don and Rosie 10 months into their marriage in New York City, when Rosie suddenly announces she is pregnant. As Don prepares for fatherhood, he fears he is unfit to be with Rosie and their unborn child. The Rosie Series concludes with The Rosie Result (2019), which features Don and Rosie struggling to help their son with Autism Spectrum Disorder (ASD) thrive. Overall, the Rosie Series gained attention and praise for its sympathetic portrayal of a neurodivergent protagonist.

This guide is based on the 2014 Simon & Schuster hardcover edition.

Content Warning: This guide describes and discusses the source text’s depiction of ableism, drug addiction, suicidal ideation, and murder-suicide induced by postpartum psychosis. The source text also includes outdated and offensive terms to refer to refer to people with Autism Spectrum Disorder, which this guide replicates only in direct quotations.

Plot Summary

Don Tillman, a visiting genetics professor at Columbia in New York City, is a person who prefers plans, schedules, and logical explanations for things. Thus, he is shocked when his wife of 10 months, Rosie Jarman, announces she is unexpectedly pregnant. His emotional meltdown makes him fear he is not equipped to be a father. This fear is underlined by a past lunch with friends and new acquaintances, when social worker Lydia told Don never to have children. He adores the spontaneous Rosie but fears she will grow weary of him. He works hard to understand social cues and empathy, and his friends Dave and Sonia—who are also newly pregnant due to IVF—reassure him. Don decides not to tell Rosie about Lydia’s assessment of him, or fellow professor Gene’s impending stay at their home to escape his wife Claudia—whom he cheated on.

Don receives conflicting messages about whether his traits are strengths or weaknesses. At his part-time bartending job with Rosie, he is treated as entertainment for his ability to recall cocktail ingredients; patrons compare him to Rain Man, a film character on the low-functioning end of the autism spectrum. When Don is reluctant to serve a celebrity whom he thinks is pregnant, he and Rosie are fired. However, his memory is valued by George, one of Dave’s clients with a beer cellar. Eventually, Gene arrives, and while he is able to coach Don on neurotypical responses to fatherhood, his ability to discuss Rosie’s emotional state casts a poor light on Don’s more clinical approach. When he follows Gene’s advice to observe children playing, his inability to read social cues leads to apprehension by police. Lydia is the social worker who takes his case, and he feels even more concerned about proving himself. Rather than distress Rosie with the incident, Don asks Sonia to pose as Rosie in an interview with Lydia. Lydia is unconvinced that Don is an appropriately supportive partner.

Don’s endeavors to support Rosie are comically insufficient: He moves them into George’s beer cellar to provide more living space, but this results in an extra bathroom as an office, the pervasive smell of beer, and occasional noise. His attempts to help Gene repair his marriage and counsel his children result in less time with Rosie. Furthermore, Don’s talk of nutrition and ultra-safe strollers displeases her. Though she is struggling with the statistics portion of her PhD thesis, Rosie does not accept his help. When Columbia’s dean assigns him to a research project about the effects of female and male caregivers on infants, Rosie doesn’t want to hear Don talk about it.

Don and Rosie’s wedding anniversary dinner leads him to believe their relationship is improving, but then he misses her first ultrasound appointment. Later, he is turned into a spectacle at a Good Fathers program when the participants learn of his martial arts training, but the moderator is convinced he would never harm anyone. He prepares for fatherhood by drawing a diagram of his baby’s weekly development on his bathroom-office wall and taking friends Dave, Gene, and George to a pregnant cow’s birth. Rosie sleeps in her study, which Gene claims is her withdrawing from marriage. When Don volunteers clinical information during a meeting for expecting parents, Rosie admits she is embarrassed by him. She decides to return to their original home of Melbourne, Australia, to raise their baby alone, and Don stays with Dave and Sonia. With Sonia’s help, Don creates an accounting system that saves Dave’s business.

Gene, Dave, and Sonia all think Don should win Rosie back. Don schedules a fancy dinner, but when he goes to their apartment to meet Rosie, he meets George’s son, who suffers from drug addiction. He suspects the young man is in distress and foregoes his dinner with Rosie to locate George, thus reuniting father and son at the cost of repairing his marriage. Don’s friends think he is underestimating himself and arrange a meeting with Lydia. She admits she was quick to judge Don because of a past patient’s inattentive husband. Suddenly, Sonia goes into premature labor, and Don and Rosie stabilize her until paramedics arrive. Rosie insists on leaving and shows Don the spreadsheet she made to support her decision. Don’s friends convince him that her calculations are wrong, and he rushes to buy a plane ticket to accompany Rosie on her flight from New York City to Melbourne, Australia. He is mistaken for a terrorist, and the plane is rerouted back to New York City.

Gene insists that Don and Rosie attend a party at Columbia. Rosie sees Don’s diagram of their baby’s development and cries at footage of him playing with a baby in his assigned research project. At his apartment, Don’s friends celebrate the ways he has helped them. Persuaded, Rosie decides to stay with Don. They fly back to Melbourne, Australia, for their son’s birth and name him Hudson.