Waterboys tells a humorous and moving story of the evolving relationship between crime novelist Victor (Leopold Witte) and his cello-playing son Zack (Tim Linde). When Zack is dumped by his girlfriend and Victor is dumped by Zack's mother on the same day, the two men grieve and briefly console one another before heading off on a trip to Scotland where Victor hopes to promote his latest book and spend some bonding time with Zack. Victor's selfish tendencies nearly alienate the fragile relationship he shares with his son, and the trip becomes increasingly turbulent as the reasons for the pairs' domestic troubles come to light.