Mary Reilly (1990) by Valerie Martin is a historical novel inspired by Robert Louis Stevenson's The Strange Case of Dr. Jekyll and Mr. Hyde. The story is narrated through the journal entries of Mary Reilly, a housemaid who works for Dr. Jekyll. In Martin's retelling, Mary, a sensitive and intelligent woman from a poor background, becomes closely involved with Jekyll, who treats her kindly after she shares her traumatic childhood experiences. As she observes his increasingly strange behavior, Mary becomes suspicious of Jekyll's mysterious alter ego, Mr. Hyde. The novel explores themes of devotion, secrecy, and duality, as Mary grapples with the unsettling transformation of her employer. Eventually, Jekyll's darker side overpowers him, leading to his tragic end, while Mary remains loyal despite the horrors she witnesses. The novel blends suspense and emotional depth, with a poignant conclusion that reaffirms Mary's enduring connection to Jekyll.