Cassidy is a twelve-year-old outsider who survived a near-drowning incident that left her with the ability to cross the Veil between the living and the dead. Armed with her beloved vintage camera, she views the world through its lens to better understand the paranormal entities she encounters. She feels deeply isolated from her peers but is fiercely loyal to her supernatural best friend.

Jacob is a teenage ghost suspended in a state of perpetual childhood who acts as Cassidy's best friend. Having saved her from drowning, the two share a profound and mysterious link that keeps him tethered to the living world. Despite his spectral nature, he is highly anxious, fears other ghosts, and prefers reading comic books to haunting humans.

Lara is a polished, independent Londoner temporarily staying in Edinburgh with her great-aunt. Like Cassidy, she has the rare ability to cross the Veil, a skill she uses to actively reap ghosts and free them from their loops. She operates with a methodical, confident approach that contrasts sharply with Cassidy's hesitant curiosity.

The Raven In Red is a legendary, malevolent spirit roaming the haunted streets of Edinburgh. According to local folklore, she is a grieving mother who lost her own child to the cold and now steals the life force of other children. She is drawn to the living who stray too far into the Veil and views them as resources for her own return to life.

Cassidy's parents, known professionally as The Inspecters, are a famous paranormal research team traveling the world. Mr. Blake is a historian and skeptic who focuses on dates and facts, while Mrs. Blake immerses herself in the cultural mythology and believes in the stories they cover. They are loving, attentive parents who remain completely unaware of their daughter's actual supernatural abilities.

Findley is a burly, knowledgeable Scottish tour guide who resembles Hagrid. He is an expert in local ghost lore, guiding the Blakes through Edinburgh's darkest and most historic locations. Though he treats the tours as historical entertainment, he holds a deep, quiet respect for the actual spiritual energy of his city.

Mrs. Weathershire is the welcoming proprietress of The Lane's End, a cozy but historically rich lodging house in Edinburgh. She easily shares the haunted history of her home and provides the Blakes with her late husband's extensive research journals.

Reginald is Mrs. Weathershire's late husband and Findley's former friend. During his life, he was fascinated by Edinburgh's folklore and meticulously documented accounts of ghost sightings, research that proves invaluable to the Blakes' documentary.

Grim is the Blake family's pet cat, who serves as the unofficial mascot for their paranormal book covers. Despite the family's unusual travels, Grim possesses a typical feline disdain for pet carriers and routine disruptions.

Matthew is a young boy lost to the cold winters of Edinburgh's past. He becomes part of the tragic loop of spirits haunting the city's graveyards, forever trapped in the folklore of stolen children.