Lisa Jewell delivers a gripping psychological thriller that weaves together three perspectives around a shocking discovery in a Chelsea mansion. When Libby inherits a house where a mass suicide occurred 25 years earlier, she unknowingly sets in motion a reunion with Henry and Lucy - survivors of the cult-like family that once lived there.

Jewell excels at creating deeply flawed, compelling characters whose damaged psyches feel authentic rather than manipulative. Henry's narcissistic charm masks genuine menace, while Lucy's fierce protectiveness of her children drives much of the tension.

The alternating timelines between past and present build suspense effectively, though some readers may find the multiple POVs initially confusing. The book tackles heavy themes including child abuse, manipulation, and trauma with sensitivity, never exploiting these elements for cheap thrills.

Jewell's prose is accessible and propulsive - this reads like a page-turner without sacrificing psychological depth. The cult dynamics feel researched and believable, avoiding sensationalism while still delivering genuine chills.

However, the resolution relies on some convenient coincidences, and certain plot threads feel rushed in the final act. The pacing occasionally stalls in the middle section as Jewell juggles multiple storylines. This book will appeal to readers who enjoyed 'Big Little Lies' or 'Gone Girl' - those who like their thrillers grounded in character psychology rather than action. Fans of domestic suspense and family secrets will find plenty to sink their teeth into. Skip this if you're sensitive to child abuse themes or prefer straightforward linear narratives. Also not ideal for readers seeking cozy mysteries or light beach reads - the subject matter is consistently dark. Overall, 'The Family Upstairs' succeeds as an intelligent thriller that respects its audience while delivering genuine surprises.