Will is the youngest of nine children living in a rural English village. As he approaches his eleventh birthday on Midwinter Day, he notices animals reacting to him with sudden fear and experiences blasts of unnatural cold. He soon learns he is the last of the "Old Ones," an immortal group tasked with defending the world from the Dark. He bears the heavy responsibility of seeking out six magical Signs to repel this ancient evil.

A white-haired immortal known as the first of the Old Ones. He serves as a mentor to Will, introducing the boy to his true nature and the perilous quest ahead. Merriman carries centuries of experience, making him deeply knowledgeable but occasionally distant from mortal concerns and emotional needs.

An enigmatic figure who carries a heavy magical burden. Introduced initially as a ragged tramp roaming the countryside, he has a complex history tied to Merriman from the thirteenth century. He finds himself caught between the forces of Light and Dark as resentment over past treatment clouds his loyalties.

A sinister figure associated with the forces of the Dark, riding a menacing black horse. He possesses unnatural red hair and operates under the name Mitothin. He seeks to thwart Will's quest to gather the Signs and acts as the primary agent of destruction attempting to overtake the world.

An ancient Old One with a musical voice who resides in a great hall outside of normal time. She aids Will in his early trials and demonstrates significant power in repelling the Dark. Her magical exertions require her to retreat and recover her strength.

A local farmer and neighbor to the Stantons who understands more about the magical world than he openly admits. He gives Will an iron cross-quartered circle ornament to wear on his belt for protection against the gathering storm.

A farmhand working on the Dawson property who is secretly one of the Old Ones. He provides critical guidance and physical assistance to Will when the forces of the Dark launch their final assaults in the winter snow.

A blacksmith and the son of Old George. He recognizes the immediate dangers of the Dark and provides Will with a magical white mare to travel safely, shielding the boy during an early encounter with the Rider.

A seemingly ordinary dairy maid working at the Dawson farm. She harbors dangerous secrets and actively aligns herself with the forces of the Dark to obstruct Will's quest for the Signs.

The wealthy lady of Huntercombe Manor. She offers her expansive home as shelter to the village during a severe, unnatural winter storm, using her position to quietly support the gathering of the Old Ones.

Will's father is a jeweler and a practical man who runs a large, bustling household. He is the seventh son of a seventh son, though he remains unaware of the magical implications of this lineage and prefers to rely on common sense.

Will's mother manages the daily operations of a household with nine living children. She remains focused on practical matters like cooking and holiday preparations, unaware of the cosmic battle occurring around her home.

Will's oldest brother, who serves in the Navy and travels the world. Will idolizes him deeply, keeping a small shrine to him in his bedroom. Stephen represents the adult world that Will is rapidly entering.

The second oldest of the Stanton siblings. Like many in his family, he possesses an artistic inclination and remains generally supportive of the younger children during the chaotic holiday season.

One of Will's older brothers and a twin to Robin. He is a highly talented flutist whose musical abilities set him apart, giving him a unique, unspoken empathy for Will's distinct nature.

Paul's twin brother. He is athletic and pragmatic, preferring sports over singing, though he shares the family's general musical background.

Will's fourteen-year-old sister. Her ordinary teenage preoccupations and vanity over her hair unwittingly make her a target for the Rider, who uses her as leverage against Will.

The second youngest Stanton sibling, making him the closest in age to Will. Practical and down-to-earth, he frequently accompanies Will on chores but rationalizes away the strange occurrences surrounding his brother.

Will's oldest sister. She plays a practical role in managing the large Stanton household, assisting her mother with cooking and daily chores.

The second oldest of the Stanton daughters. She blends into the chaotic but loving background of the large family during their Midwinter preparations.

The Stantons' firstborn child who died after only three days. His brief existence is vital to Will's destiny, as it technically makes Will the seventh living son of a seventh son.

An archetypal figure tied to English folklore, bearing the antlers of a stag. He slumbers in the shadows until Will summons him to lead the red-eared hounds of the Wild Hunt against the darkness in the sky.

A Dark Ages champion of the Light resting on an ancient Viking ship that rises from an island in the Thames. He waits across centuries to pass a crucial artifact to the newest Old One.