Christmas thought her ADHD was a liability. Turns out, it is a superpower. Seventeen-year-old Christmas Miller is looking forward to a summer of sunbathing and waterskiing at her home in Sweet Lake with Lexi, the one friend who gets her completely, ADHD and all. But the day of Lexi's arrival, the girls have an almost-argument and worse, that night, they discover another friend, Lemy, floating face down in the lake. Though reeling from her rift with Lexi, Christmas is determined to find out who attacked Lemy, even if it means she must confront her own mother's possible involvement in the crime.

Christmas would do anything to protect her beloved Sweet Lake community, but when the lake becomes polluted and people around her start getting hurt, Christmas must face the profound problems in Sweet Lake—and in her own family.