The Nanny exerts a powerful influence over the Fane family. Seth Holt directed The Nanny, with a screenplay by Jimmy Sangster based on Evelyn Piper’s (also known as Merriam Modell) novel of the same name. It features performances from Bette Davis, Wendy Craig, William Dix, Jill Bennett, James Villiers, and Pamela Franklin. Richard Rodney Bennett composed the music, and Harry Waxman was in charge of cinematography. The film centers around the Fane family, their Nanny, a past tragedy, and young Master Joey Fane recently released from an institution for troubled children. Hidden truths are destined to surface. This psychological thriller from Hammer Film Productions is noteworthy due to its well-crafted narrative and strong acting, particularly from Bette Davis. While the mystery aspect of the plot doesn’t quite manage to fully engage, because the film's title gives away what's amiss within the Fane household, the ongoing conflict between young Joey (Dix delivers a compelling performance as a child who is both defiant and aggressive yet detached) and Nanny Bette remains captivating. Holt develops the story at a deliberate pace; the Fane home is filled with tension. Craig portrays a mother on the verge of collapse, Villiers plays a distant father who isn’t present enough to connect emotionally with his wife and son. Overseeing them all is the Nanny, moving effortlessly among them, maintaining control with an unsettling composure—a calm before the storm. The film's impact is heightened by the production team’s measured and unhurried approach once the revelations begin to emerge. The movie is effectively filmed in black and white and mostly takes place within a single home, creating a palpable atmosphere and a sense of oppression. The mystery element isn’t as compelling as it could be, and the ending feels somewhat underwhelming, preventing it from reaching the highest ranks of Hammer's psychological horror films. Nevertheless, it’s an accessible recommendation for fans of the genre, especially those who appreciate Bette Davis’s undeniable presence. 7.5/10

Source on TMDB