Beautiful, Fearless, Dangerous. They're the kind of girls you envy; the kind of girls you want to hate. Strangers in town for the summer, Penn, Thea and Lexi have caught everyone's attention, including the eye of practical Harper. But it's her sister, Gemma, they've chosen to be part of their group. Sixteen year old Gemma seems to have it all - carefree, pretty and falling in love with the boy next door. But her passion has always been the water, she craves late night swims and lately she has company in Penn, Thea, and Lexi. When she wakes up groggy on the beach the next morning, she knows something has changed....