Marty is the eldest child in the Preston family, living in a close-knit West Virginia community. He has a strong sense of right and wrong, having previously rescued his dog, Shiloh, from an abusive neighbor. As he observes the town's ongoing hostility toward that neighbor, Marty begins to develop a more mature understanding of morality, empathy, and forgiveness.

Judd is a local man with a troubled past that includes alcohol addiction and a history of animal abuse. He is recovering from a drunk-driving accident that nearly cost him his life. Despite his rough exterior and the community's deep distrust of him, he shows tentative signs of wanting to change and improve his life.

Shiloh is a beagle whom Marty rescued from Judd Travers. Though he is deeply devoted to Marty and the Preston family, he remains fearful and anxious around his former owner. Shiloh is a constant source of joy for Marty, though his presence also complicates Marty's interactions with Judd.

Dara Lynn is Marty's younger sister. She frequently antagonizes Marty and strongly desires a pet of her own, particularly a kitten. She provides a consistent source of sibling friction in the Preston household, testing Marty's patience.

David is Marty's best friend. As the son of a newspaper reporter, he has a flair for the dramatic and loves to formulate wild theories, especially regarding local crimes. He often voices the town's collective suspicion against Judd Travers, acting as a foil to Marty's growing empathy.

Marty's father is a fair-minded man who encourages his family to be neighborly. He hunts for food but sets a positive example of empathy by insisting that Judd deserves a chance to turn his life around. He places responsibility on Marty to act as a role model for his younger sisters.

Marty's mother is a compassionate woman who takes the initiative to invite the socially isolated Judd Travers to their family Thanksgiving dinner. She works to maintain harmony in the household and supports her children while managing the challenges of living in a small, rumor-prone town.

Becky is Marty's youngest sister. She is innocent, occasionally blunt, and follows the lead of her older siblings. Her direct questions, such as asking what a Thanksgiving turkey's name was, sometimes cause tension during awkward social situations.

Mr. Howard is David's father and a reporter for the local newspaper. He is often the source of town news and gossip that filters down to David, keeping the boys informed about local mysteries and police investigations.

Dr. Collins is the local veterinarian who employs Marty. He provides Marty with practical advice on animal care, including the suggestion that a fence would greatly improve the temperament of chained dogs.

Doc Murphy is the local physician for whom Marty occasionally does yard work. He is a pragmatic man who agrees to give Marty his old garden fence to help Judd's dogs.

Grandma Preston is Marty's elderly grandmother who lives in a nursing home in Clarksburg. She suffers from dementia, which causes her to be forgetful and occasionally combative with the staff and other residents.

Mrs. Howard is David's mother. She displays the typical town skepticism regarding Judd Travers and questions Marty about his behavior.