Naum Yegorovich, an agent embedded in the secret, closed laboratory “Blue Bird,” is forced to share a ward with a strange “neighbor”—a witcher, Zhenya. While the staff prepares him for dubious “procedures,” something ancient and dangerous is maturing in the basements, and outside, a different story unfolds. A young witch, Ulyana, is only just learning to control her awakening gift, as well as the crushing weight of family debts and her own curse. In her home, shelter is found for runaway teen Satanists, talking goats, and imperial mice. The investigation leads her to Danila, and from him—to the secrets of “Blue Bird.” Intertwining with the fate of the agent who finds himself trapped, Ulyana must decide: should she save her loved ones before the dark force, fed by human lives, is ready to swallow everyone.