The Lake centers on the quintessential Canadian cottage experience. Justin returns from living abroad after a break-up with his long-term partner, in the hope of reconnecting with the biological daughter that he gave up for adoption in his teens. His plans to create new memories with his city-loving daughter Billie at the idyllic lake from his childhood go awry when he finds out his father left the family cottage to his "picture-perfect" stepsister, Maisy-May.