Tuck is a character from the novel "Tuck Everlasting" by Natalie Babbitt. He is a member of the Tuck family, who have gained immortality after drinking from a magical spring. Tuck struggles with the consequences of living forever, feeling that eternal life is more of a burden than a blessing. In the story, Tuck meets a young girl named Winnie Foster, who is curious about his family's secret. Through their conversations, Tuck shares his experiences and the challenges of immortality, ultimately teaching Winnie about the value of life and the natural cycle of death.