The unicorn collection belonging to Linda the blonde is a juxtaposition to her character. The unicorn symbolism is usually attached to chastity and virginity (as depicted in the Medieval Arts) whereas her job is implied to be a sex worker or escort. Her red apartment alludes to a "red-light district".
The film is based on Donato Carrisi's 2017 novel "Into the Labyrinth" (original Italian title: "L'uomo del labirinto")
In this film and Donato Carrisi's previous film "Girl in the Fog" (2017) is the repetitive use of the number 23. The significance of the number 23, known as the "23 enigma" has been popularized by various books, movies, and conspiracy theories. Donato Carrisi's number 23 is used in his films as an unlucky number associated with murder, death, and danger. In Italian history, for example, the Roman general Julius Caesar was stabbed 23 times.