S. J. Watson's 'Before I Go to Sleep' is a masterful psychological thriller that plunges readers into the terrifying world of Christine Lucas, a woman who wakes up every day with no memory of her past. Suffering from a rare form of amnesia, she relies on her husband, Ben, to reconstruct her life. However, a secret journal, urged by her doctor, reveals shocking entries that contradict Ben's account and raise unsettling questions about her true identity and the secrets her past holds. This gripping novel brilliantly explores themes of memory, trust, and the fragile nature of perception, keeping readers on edge until the very last page. It's a compelling exploration of what happens when your own mind betrays you.