On the tropical island of Bora Bora, honeymooners Mark and Erin go scuba diving. Mark is with her - Erin knows he'll keep her safe. Everything will be fine. Until they find something in the water. They decide to keep their discovery a secret - after all, if no one else knows, who would be hurt? Their decision will trigger a devastating chain of events, which will endanger everything they hold dear. A Reese Witherspoon Book Club pick.