The Housemaid Series in Order by Freida McFadden

Millie Calloway takes a job as a live-in housemaid for the wealthy Winchester family, only to find herself entangled in their disturbing secrets and lies. As Millie uncovers the truth, she realizes that escaping the sinister household may be more difficult than she ever imagined.

Millie starts a new job as a housemaid for another seemingly perfect family, only to discover that they, too, harbor dark and dangerous secrets. As she navigates the treacherous waters of deception and manipulation, Millie must use all her wits to survive the looming threats.