A reclusive man living in a secluded house on Lake Burton, Georgia, hiding from his past as a brilliant heart surgeon. He spends his days restoring old boats alongside his brother-in-law and avoiding close connections with others. His quiet, reserved nature masks a deep sense of guilt and exhaustion from his previous medical career.

Reese's late wife and childhood best friend, whose severe heart condition originally inspired him to enter medicine. She serves as a guiding memory for Reese, representing both the love of his life and his greatest perceived failure. A talented artist, she lived her life with optimism and spiritual faith despite her physical limitations.

A spunky, seven-year-old orphan who lives with her aunt and suffers from an enlarged heart. Described as having a "tomboy's heart in a china doll's body," she raises funds for her own medical care by selling lemonade and bait crickets. She approaches her severe health condition with remarkable joy and a steady belief in a better future.

Annie's devoted aunt and guardian who took the young girl in after her missionary parents died. She struggles under the weight of mounting medical debt, working long hours and desperately seeking loans to afford Annie's care. Despite her exhaustion and frayed nerves, she remains fiercely protective of her niece.

Emma's brother and Reese's closest companion, living in the house directly across from him. Blinded by a tragic accident in the past, he moves through the world with unfettered optimism, taking dance classes and building boats. He acts as Reese's anchor, offering nonjudgmental friendship while keeping the secret of his brother-in-law's former life.

The enigmatic owner of a local eatery called The Well, which he constructed from large stones and old wood. Known as "Monk" due to time spent in a Spanish monastery, he views his bar as an alternative ministry for those running from their pasts. He subtly incorporates Scripture into the decor and serves watered-down beer to protect vulnerable patrons.

A sixteen-year-old boy running from past mistakes who frequents the local lake area. He wrestles with bad habits, including substance use and hostility toward authority. His abrasive exterior masks a confused teenager in need of positive role models.

A cardiologist practicing in Atlanta who currently manages Annie's failing heart condition. He previously worked alongside Reese in the high-pressure world of cardiac surgery and recognizes his old partner despite Reese's attempts to hide his identity.

Reese's former medical school mentor at Harvard. He played a crucial role in pushing Reese toward his specialty in cardiac surgery, occasionally using dramatic tests in the operating room to evaluate his students' composure under pressure.