When We Believed in Mermaids is a bestselling novel by author Barbara O’Neal. Set primarily in New Zealand, the novel tells the story of Kit and Josie Bianci, sisters who survived neglectful parents and abuse. When Kit sees news footage of her sister Josie on the television 15 years after her reported death, Kit travels to New Zealand to find her sister, and, in the process, finds love, hope, and acceptance. Released in 2019, When We Believed in Mermaids appeared at the top of Amazon’s most read book list in 2020.

This guide references the Kindle e-book published by Lake Union Publishing.

Content Warning: The source material for this guide includes descriptions of alcohol/drug addiction and recovery, the sexual assault of a child, suicidal ideation, abortion, and parental neglect.

Note: Mari is the adult alias of the character of Josie Bianci. Mari considers her childhood self, Josie, to be “dead” for much of the novel. When referencing flashbacks or memories in this guide, the name Josie is often used instead of Mari, while Mari is used to represent her present self. A combination of the two, Josie/Mari, is used when necessary.

Plot Summary

Dr. Kit Bianci is taking a break from a hectic night shift in the emergency room when she catches a few seconds of a news report concerning a fire in a nightclub in Auckland, New Zealand. In the background, Kit sees a woman who looks exactly like her sister, Josie. However, Josie supposedly died in a terrorist attack in Paris 15 years prior. When Kit returns home after her shift, she receives a call from her mother, who saw the same news report. Kit’s mother asks Kit to go to New Zealand and find out if the woman in the news footage is Josie.

Upon her arrival in New Zealand, Kit begins brainstorming ways to find Josie as she explores the Central Business District (CBD) and surrounding areas. She goes to a local Italian restaurant for dinner and runs into a man from Spain, Javier, who is also staying in her high-rise building. They share a bottle of wine and conversation before he takes her to listen to music at a nearby Spanish restaurant. When Javier gets up to sing, Kit leaves because she would prefer not to get involved with a man she might catch feelings for.

Across the island, Josie—who now goes by Mari—learns that her husband has bought her a house that she has admired since moving to New Zealand. This house is referred to as Sapphire House. The house was built and owned by a famous actress from the 1930s, Veronica Parker. Veronica was murdered in the house, but her killer was never identified. Her sister, Helen, inherited the house and lived in it until her death just a few weeks prior. Mari is excited to begin renovating the house for her family.

As Kit searches for Josie and Josie/Mari begins work on Sapphire House, they both begin remembering events from their childhood. They lived on a cliff outside Santa Cruz in a house beside the restaurant, Eden, that their parents owned. The restaurant was popular, and the girls were expected to work there even as young children. Kit and Josie’s parents were self-centered and passionate people who had little time to be proper parents. It wasn’t until a lost little boy showed up at their door, Dylan, that the girls had someone to look out for them.

As Mari finds herself thinking about the past, she acknowledges that faking her death likely saved her life as it helped her recover from her addiction, but she misses her sister. At the same time, Kit is in the CBD asking around at local businesses for any information on Josie/Mari. Kit reconnects with Javier, and they become lovers. Kit tells Javier about her search for her sister and some of his suggestions give her the idea to call around to surf shops, as her sister loves to surf. Kit finds a shop where the clerk is able to give Kit Mari’s name. Kit uses this name to look Mari up on the internet and discovers that her sister has gotten married and has two children, including a daughter who looks like Kit.

As Kit searches for her, Mari continues to remember her past. Mari remembers how Dylan bore scars of abuse and turned to alcohol and marijuana to deal with the pain of it. She also recalls how he tried to protect her and Kit. However, Dylan couldn’t protect Josie from the actor, Billy Zondervan, a regular customer of her parents’ restaurant who sexually assaulted her. Josie eventually told Dylan the truth, but he kept it to himself. Dylan introduced Josie to marijuana, leading her to try other drugs and to continue the alcohol consumption that began when Josie was young.

Mari recalls Dylan being kicked out of the house after a confrontation with her father. A few days later, he was in a motorcycle accident and had to recover at the house. A few months into Dylan’s recovery, Josie/Mari’s parents left for two weeks to attend a restaurant conference, and Kit went to a camp for perspective medical students. Both left alone, Josie convinces Dylan to leave his room and they fall into their pattern of drug and alcohol misuse. One night, while intoxicated on cocaine, Josie, who is underage, and Dylan have sex on the beach at Josie’s repeated insistence. Dylan grew distant from her after this, and a few weeks later, Dylan died by suicide. After Dylan’s death, Josie/Mari discovered she was pregnant. Her mother took Josie/Mari for an abortion. Afterward, an earthquake hit the area. Josie/Mari was hit on the head by falling debris and it took hours for her to be treated by medical personnel. By the time they reached home, Kit had been sitting on the street for hours. The house and restaurant had fallen over the cliff, killing their father in the process.

Kit finds Mari’s address and attempts to drop in on her but runs into her on the street instead. Mari asks Kit not to tell her family her real name. Kit is angry, but she falls instantly in love with Mari’s daughter, Sarah, and chooses not to say anything for her sake. Kit and Mari meet the following day, and Mari explains about the terrorist bombing that Kit had thought killed Josie/Mari 15 years before. Mari then explains how she came to New Zealand and is successfully in recovery from drug and alcohol addiction, after which she met her husband, Simon. Mari tells Kit that she has been flipping houses for years, and that she is using her skills to prepare Sapphire House for her family.

Kit visits Mari’s home that night for dinner, and the awkwardness and Kit’s resemblance to Sarah alerts Simon to the lies Mari has been telling him. Mari comes clean and convinces Simon over several conversations not to end their marriage. At the same time, Kit returns home, struggling to reconcile everything she learned about Josie and Dylan in her recollections. After a month back home, Kit is surprised when Mari, her family, and Javier come to visit. Javier convinces Kit he loves her. Mari and Kit surf, putting to rest the ghosts of their past.