The Snorkel (1958)

Plot

On the picturesque Italian coast, writer Paul Decker finds himself disillusioned with his marriage and orchestrates what seems to be a flawless murder of his wife. While he’s presumed to be penning a novel in France, his stepdaughter, Candy, harbors doubts about his innocence, suspecting him of both her mother’s death and her father’s from years prior. With law enforcement dismissing her concerns, Candy embarks on a perilous quest to gather evidence and bring her sinister stepfather to justice.