It is the summer of 1972. Thirteen-year old Janey and her parents settle into their isolated beach house for another idyllic seaside holiday. Janey's parents distract themselves from their increasingly distant marriage by drinking away their nights and sunbathing their hangovers. Meanwhile, Janey and her kid brother spend their unattended days playing by the ocean. Holding tight to her waning sexual allure, Janey's mother, Kate, has eyes for a drifter photographer who becomes the latest battleground in the quiet war between mother and daughter. Angered by her mother's infidelity, Janey begins to discover the power of her own sexuality, acting on her desires in increasingly reckless ways. As she rushes headlong into dark, adult waters, Janey is soon confronted with the terrible realization that in a moment everything can change forever.