It's blue. It's dark. It's cold... They call it the Blue Hole.

For years, teenagers have gathered for parties along the banks of the deep swirling pool of water called, The Blue Hole. Bon fires, loud music, and kegs propped up on tailgates were the common themes. The parties would rage on all night long. But in one night, everything changed.
Seven years ago, Jill Turner's twin sister, Samantha, disappeared after a party at the Blue Hole. Her jacket was discovered at a bus stop in the next town over which suggested she had run away, but her family wasn't convinced. After a mysterious letter is slipped under the front door of her home, Jill is prompted to search for answers.
What really happened that night at the Blue Hole seven years ago? In order to answer that question, Jill must put her own complicated life on hold, and dive head first into the secret perilous life her sister once lived.