She sees him too late—a dark shadow by her apartment door. Rushing down the flight, she tries to cry for help, but the words won’t come. A glint of steel is the last thing she remembers before the darkness swallows her whole.

When a 20-year-old Alisa Feoktistova disappears from her own stairwell, leaving behind only a pool of her blood, it becomes clear a new serial killer is on the loose in Moscow. He’s believed to have taken at least three people before Alisa, each time marking the crime scene with an ample amount of victim’s blood, which earned him a nickname Bloodletter.

Are all his victims dead? Or is there a chance Bloodletter keeps them alive, despite the blood loss?

One thing is for sure: private investigator Zoya Volkova won’t let go of this case. Years ago, her little brother went missing in a similar manner, a pool of blood glistening in the middle of the empty apartment. What if it wasn’t the doing of Zoya’s mother, like the judges decided, but of some bloodthirsty monster who avoided the justice then and now kills again?

Uncovering the connection between the victims, Zoya stumbles into a decade-long conspiracy in the heart of a Moscow hospital. She can’t trust anyone—not even Alisa’s family—as she untangles a knot of betrayals, medicine taboos, and stigma. She only knows that Bloodletter’s killing rampage is not over and more innocent lives are on the line.

Zoya will stop at nothing to save a life. But will she be able to find the truth before Bloodletter swings his blade at another victim’s throat?