Will is a 12-year-old boy from Winchester, England, who acts as the primary caretaker for his mother. Conditioned to hide in plain sight, he is fiercely protective and highly resourceful. After an incident at his home forces him to flee, he travels through a dimensional window to a deserted city, beginning a search for his missing father.

Lyra is an independent, headstrong 12-year-old from a parallel version of Oxford. Raised by scholars, she possesses a natural talent for reading an advanced truth-telling device called an alethiometer. She travels across worlds seeking answers about a mysterious elementary particle called Dust.

Serafina is the gentle but authoritative queen of the Lake Enara witch clan. She flies through different realities to locate and protect Lyra. Opposing the oppressive religious authorities in her world, she uses her longevity and flight to coordinate a growing rebellion.

Lord Asriel is an ambitious and commanding explorer from Lyra's world. He builds a massive army in a northern fortress to wage war against a supreme religious authority figure. His grandiose self-image makes his true loyalties and ultimate plans difficult to determine.

Lord Boreal is a manipulative associate of Mrs. Coulter. Operating across dimensions with his snake daemon, he tracks valuable artifacts and seeks a weapon capable of cutting through worlds. He uses his considerable wealth and influence to fund scientific research that aligns with his personal goals.

Mrs. Coulter is a brilliant and striking woman aligned with the powerful Magisterium in Lyra's world. She commands an army of soul-eating creatures and relentlessly hunts down anyone who opposes her religious doctrine. She travels with a creeping monkey daemon who silently spots intruders.

John is an English explorer and Will's missing father. He vanished during an Arctic expedition twelve years ago. He functions as the primary motivation for his son's journey, having left behind correspondence detailing exact coordinates to dimensional gateways.

Ruta is the Croatian witch queen who joins forces with Serafina Pekkala. Known for her ruthless and aggressive personality, she leads her own followers with total loyalty. She actively seeks out Lord Asriel's fortress to offer military support for his coming war.

Lee is a skilled balloon pilot and explorer from the sovereign nation of Texas in Lyra's world. He possesses an extensive knowledge of Arctic customs and languages. He flies through perilous skies to locate a legendary missing explorer, refusing to back down from heavily armed soldiers.

Mary is an Oxford physicist and former nun who researches a phenomenon known as dark matter. Operating out of a severely underfunded laboratory, she discovers that subatomic particles can connect with human consciousness. She uses a computer system to communicate directly with this mysterious matter.

Oliver is a stressed researcher working alongside Mary Malone in an Oxford physics laboratory. Frustrated by budget constraints and professional instability, he readily accepts suspicious defense funding offers to keep their project afloat.

Paolo is a young boy surviving in the abandoned seaside city of Cittàgazze. Unaffected by the invisible creatures that attack adults, he roams the empty streets with his sister and treats the lack of supervision as an extended vacation.

Angelica is a child living in Cittàgazze alongside her brother Paolo. She eagerly accepts the freedom of an adult-free city but harbors violent tendencies when she believes outsiders have harmed her family.

Tullio is an aggressive young man in Cittàgazze attempting to steal a powerful artifact. He desperately fights to obtain a magical blade to protect himself from the soul-draining creatures roaming the city.

Giacomo is an elderly man residing in a mysterious tower in Cittàgazze. He guards a weapon capable of slicing through dimensions and formally instructs its new bearer on how to wield it safely.

Lena is a witch traveling with Serafina Pekkala's clan. She spies on enemy forces to protect her allies during their trek across treacherous mountainous terrain.

Pantalaimon is Lyra's daemon, serving as the physical manifestation of her soul. Because Lyra is still a child, he constantly shape-shifts into various animals to reflect her current emotional state and physical needs.

Kaisa is a snow goose daemon bound to the witch queen Serafina Pekkala. He possesses the ability to travel vast distances away from his human counterpart to deliver messages and scout for danger.

Hester is an Arctic hare daemon belonging to the aeronaut Lee Scoresby. She remains close to the balloon pilot throughout his dangerous journey across the north, providing quiet support.

Mrs. Cooper is Will Parry's piano teacher in Winchester. She provides temporary shelter for his mother when Will departs on his journey, offering a rare source of stability for his family.

Mrs. Parry is Will's mother, living in Winchester, England. She experiences severe confusion and distress, though her intense fears about men breaking into her house to steal her missing husband's letters turn out to be completely justified.

Moxie is Will Parry's pet cat. Her presence inadvertently protects Will from an intruder before leading him toward a dimensional gateway hidden on the edge of town.