Tired of living under the strict discipline of her parents and grandmother, 10-year-old Winnie Foster decides to run away from home. She feels “cooped up” and wants to make a difference in the world. When she ventures out on her own, she discovers a young man in her family’s wood who belongs to a remarkable family with a remarkable claim: that the water from a spring in the forest has given them immortality. Mae Tuck, the family’s matriarch, kidnaps Winnie in order to keep this secret safe, but a stranger in a yellow suit is already on the Tucks’ trail, eager to exploit their secret for his own financial gain. Winnie must decide whether she believes the Tucks’ claim, if she will trust and help them, and– before her adventures end– what kind of life she will choose to live.