The Family Upstairs (2019) is a suspense/thriller novel by Lisa Jewell. The novel was an instant New York Times bestseller and a Good Morning America Cover to Cover book club pick. Jewell's other best-selling novels include None of This Is True (2023), Then She Was Gone (2017), The Girls in the Garden (2016), The Night She Disappeared (2021), and Invisible Girl 2010).

Plot Summary

The Family Upstairs tells the stories of three characters: Libby, Lucy, and Henry. Alternating third-person chapters follow Libby and Lucy’s lives as adults, alongside Henry’s memories of growing up in a mansion in Chelsea in the late 1980s and early 1990s.

At the beginning of the novel, Libby is a 25-year-old woman living in London when she receives a letter indicating she has inherited a mansion in Chelsea that belonged to her biological family. Libby doesn’t know much about her biological family because she was adopted as a baby. She quickly learns that the house has a dark past, and the novel follows Libby as she unravels the house’s mystery.

Libby finds an article that explains how a group of adults and children lived in the house. One day, in 1994, three adults—Henry Lamb, Martina Lamb, and David—were found dead by poisoning, presumably due to a cult-related suicide pact. A baby was found in a crib upstairs, alive, clean, and well fed. This baby, originally named Serenity Lamb, was Libby. After reading this article, Libby tracks down its author, Miller Roe, and the two attempt to investigate what happened to the other members of the household.

In Henry’s flashbacks, he explains how he, his father (also named Henry), his mother Martina, and his sister Lucy were a comfortable, wealthy family living in their mansion in Chelsea. In 1988, Birdie, a fiddle player for a popular band, convinces the Lamb family to let her band film a music video in the house. A few weeks later, Birdie returns with her partner, Justin, claiming they’ve been kicked out by their landlord. Martina allows them to stay at the house. Birdie convinces the Lambs to invite her friend, David, his wife Sally, and their two children, Phin and Clemency, to live at the house. She claims David’s alternative medicine practices could help with the senior Henry’s deteriorating health.

Over time, David uses his charisma to charm Martina, Birdie, and Lucy and take control of the Lamb family’s finances and household. David implements strict rules, convincing everyone to give up their belongings, wear homemade clothing, and eat a limited, meatless diet. He frequently locks the children in their bedrooms as punishment and is even, at times, physically abusive. David coerces Lucy to have sex with him. When she becomes pregnant with Libby, it’s assumed the baby is his, and he forbids Lucy from seeing the baby after she is born. However, Libby is actually the child of Lucy and Phin.

Eventually, Henry and the other children plan to temporarily drug the adults during a dinner party so they can escape. However, the night of the escape, Birdie wakes up and Henry kills her by stabbing her with a sharp object. Henry hides her body on the rooftop. Henry then discovers that the herbs he fed to the other three adults killed them. Henry stages the deaths to look like a suicide pact. Henry leaves baby Libby in her crib and anonymously calls the police, who hand the baby off to social services. Meanwhile, Clemency runs off and tracks down her mother in Cornwall. Lucy takes Phin to a doctor, who helps them escape to France.

In the present, 40-year-old Lucy is a homeless woman living in the Côte d’Azur. Knowing her baby is now 25, Lucy takes her two children from France to London and tracks down Libby at the Chelsea mansion. After meeting Henry, Lucy, and Lucy’s two children, Libby develops a close relationship with her biological mother.