In the summer of 1920, a young woman is called to work as a governess at The Hibiscus, a grand and sweeping estate on Tybee Island off the coast of Savannah, GA. She is reeling from a recent tragedy, looking for employment and a way to escape the dark reality of her life. She believes that a fresh start on the sunny southern Atlantic beaches will help to lift her spirits; instead, she only finds more doom and gloom.

Dashiel "Dash" McCray, the son of a wealthy whisky tycoon, is still wallowing in the aftermath of his own tragedy after losing his beloved wife, Elizabeth. His daughter, Penelope, is also mourning and becoming more sickly and withdrawn by the day. It is Dash's hope that a new governess imported from New York will help to lift his daughter's spirits, despite the constant reminder of their grief.

However, as soon as the new governess arrives, it is quickly made apparent to her that things at The Hibiscus aren't as they seem.