It's the summer of 1914. Eight-year-old Bernice lives with her family in a lighthouse on Georgian Bay. Bernice doesn't get to explore much farther than their island, but she has her books to fuel her imagination, including her favorite, Treasure Island. One day Bernice wakes up to find a stranger named Tom Thomson sleeping in their living room. When she overhears him talk about gold on a nearby island, Bernice is determined to find it. Inspired by her beloved Mémèr's stories of their Métis family's adventures and hardships, Bernice takes the treasure map the stranger left behind and sets out in a rowboat with nothing more than her two dogs for company and the dream of changing her family's fortunes forever.