The Innocents (1961)

The impressionable Miss Giddons is hired on by a rich Englishman as the governess to his unwanted niece and nephew, who are currently under the care of their witless housekeeper in a beautiful country estate. She quickly becomes enthralled by the two charming children and their idyllic home, but the seemingly perfect facade begins to fade away as Miss Giddons uncovers the deaths of the two