The central villain of the show's true identity remains a mystery, but he has many aliases: "Mabuse," "the Immortal Count," "the Devil Gambler," and more. Mabuse will do anything to achieve his goals, even consorting with eldritch gods.

Skyla and Jack's neighbor, Dr. Eliza Strong is friendly, nurturing, and easy-going. She is the person closest to Jack besides Skyla. Maybe this is because they're both doctors, and she allows Jack to have sense of normalcy in his life.

Detective Garfield Lestrade may be the only police officer who willingly works with Skyla. This is because is Lestrade is exhausted. He needs her help to lighten up the workload, but also because he cannot trust his fellow officers. Lestrade is the only honest cop left in the city.

Mattie Turner would rather not deal with Skyla. However, her grandmother, Mrs. Hudson, asks her to assist in the girl's investigations. This has led to Mattie becoming the "begrudging third wheel" of these investigations. She may be prickly, but she has a soft spot for kids.

Dr. John "Jack" Watson: former army surgeon, soldier, and Skyla's only friend. He's very down-to-earth, which is surprising that he is able to put up with Skyla's eccentricities. The two have an older brother-younger sister kind of relationship.

Sherlock "Skyla" Holmes, our protagonist. She is one of the smartest people on the planet, but is also moody, eccentric, and anti-social. Just don't mention her height, she's very sensitive about that.