Alan is a nervous and impulsive worrier who bets Billy can’t complete the worm-eating challenge, often resorting to tricks to derail him.

Tom is Billy's loyal friend and assistant during the worm-eating bet, who contributes to Billy's efforts and defends him against opposition.

Joe is a clever, educated friend of Alan’s who devises schemes to challenge Billy’s progress in the worm-eating challenge.

Billy’s mother is supportive and helpful throughout his worm-eating adventure, providing a stable and loving household environment.

Billy’s father is a humorous and sensible figure who reassures his family about the harmlessness of the worm challenge and brings balance to the story.

Alan's father serves as a motivator for Alan’s actions by enforcing fairness and justice among the boys.

Pete is Tom’s younger brother, whose actions help ensure fairness and completion in the worm-eating bet.