In a quiet suburban town in the summer of 1958, two recently orphaned sisters are placed in the care of their mentally unstable Aunt Ruth. But Ruth's depraved sense of discipline will soon lead to unspeakable acts of abuse and torture that involve her young sons, the neighborhood children, and one 12-year-old boy whose life will be changed forever.

A wealthy film producer Michael Pace discovers a beautiful unconscious woman pushed ashore by what appears to be a friendly dolphin. Confused and captivated by the apparent supernatural events taking place around him, Michael decides to make a film about his experience with the mysterious woman from the sea. Very soon the movie that Michael is making entwines itself into his family's past, his children's lives, and the very future of their existence together. Set at the cross roads of the modern world and ancient mystical cults, "Bad Girl Island" spins a tale of murder, obsession and seduction that leads its audience into a labyrinth of intrigue, action and mysterious forces.