Emily is a 30-year-old Cambridge adjunct professor and a leading expert on faeries. She travels to the isolated Scandinavian wilderness to study the elusive "Hidden Ones" for her research. Socially awkward and introverted, she strongly prefers the company of her books and research subjects over other humans. She relies on strict objectivity to excel in academia, which often makes her appear cold or detached from the people around her.

Wendell is a 29-year-old dryadologist and Cambridge professor who acts as Emily's primary academic rival. He is charming, highly sociable, and conventionally attractive, possessing a flawless demeanor that directly contrasts with Emily's awkwardness. He avoids manual labor entirely, delegating his fieldwork to students while relying on his charisma to manage social situations. Emily strongly suspects his peculiar habits conceal a non-human identity.

Shadow is an enormous, elderly boarhound who travels everywhere with Emily. He is blind in one eye and generally maintains a calm, docile demeanor. Despite his lethargic appearance, he provides an imposing physical presence that deters threats in the wilderness, reacting to supernatural dangers with an unusually knowing calmness.

Aud is the village headwoman of Hrafnsvik. She is a pragmatic, influential leader who watches over her community with a highly protective eye. She expects basic courtesy and respect for local customs, and she controls the village's social and economic reception of outsiders based on their behavior.

Lilja is a local woodcutter in Hrafnsvik. She is physically strong, conventionally beautiful, and generally oblivious to the supernatural elements surrounding her home. Her property is of immediate interest to Emily's research, though Lilja herself is more concerned with her mundane life and relationships.

Margret is Lilja's girlfriend. She has a bubbly, conversational personality that contrasts with the gruffness of many other locals. She takes a genuine, friendly interest in the personal lives of the visitors to Hrafnsvik.

Poe is a minor faerie, or Brownie, who resides in the forest near Hrafnsvik. He presents a childlike appearance and operates strictly through transactional exchanges. He interacts with Emily by trading goods for services, providing her with valuable bread and insight into local faerie behavior.

Krystjan is a local farmer who rents out a small, isolated cottage to Emily. He exhibits a mildly rude and skeptical demeanor toward her academic goals. He follows the village's collective mood, adjusting his treatment of Emily based on her standing with the headwoman.

Finn is Krystjan's son. He possesses a passion for baking that his father strongly disapproves of. He acts as an intermediary between Emily and the village during her initial isolation, bringing her food and basic supplies when she is unable to provide for herself.

Ulfar is the tavern owner in Hrafnsvik and Aud's husband. He is a man of few words with a sharp, brooding physical appearance. Despite his gruff exterior, he maintains the local hub where townspeople congregate to avoid the severe winter weather.

Thora is an elderly woman in Hrafnsvik. She speaks her mind directly and participates actively in the local gossip regarding the new visitors. She represents the skeptical attitude many villagers hold toward outsiders braving their harsh winter.

Auðor is Aud's niece. She is a young woman in her twenties who suffers from severe trauma after being taken by the local faeries. She moves and acts only when commanded, serving as a physical warning to others about the dangers lurking in the nearby forest.

Mord is a local villager dealing with a severe supernatural infestation in his home. He holds out hope that Emily's academic knowledge can resolve the dangerous situation terrorizing his family after their human child was stolen.

Aslaug is Mord's wife. She suffers under the constant terror inflicted by the entity that has taken over her child's body, struggling to maintain her household under severe supernatural duress.

Ari is the young son of Mord and Aslaug Samson. He was stolen from his crib five years prior by the local faeries and replaced with a courtly entity. His absence casts a heavy shadow over his parents' daily lives.

The Changeling is a courtly faerie occupying the physical form of the human child Ari. It generates terrifying mental illusions and feeds on the fear of the Samson family, acting as a disruptive, hostile presence in the village.

Henry is one of Wendell's graduate students from Cambridge. He acts more as a servant than a scholar, performing domestic chores and tidying the cottage to suit Wendell's exacting standards for comfort.

Lizzie is a Cambridge student assisting Wendell on his expedition. She follows his instructions to make the rural environment more comfortable, though she is entirely unprepared for the reality of field research in a magically active zone.