Robbie's life gets inextricably complicated when her estranged father shows up with a shocking revelation about two teenage girls who disappeared in South Beach. One of the missing girls is Robbie's sister Kate—a sister Robbie never knew existed. Unwilling to reestablish family ties, Robbie is hesitant to get involved—until the body of her sister's friend washes up in Indian Creek. Desperate to find her missing sister, Robbie immerses herself in the unfamiliar world to which Kate may have fallen prey: the sexy, sizzling South Beach club scene.