During the year, strange murders take place in Moscow and its environs, seemingly unrelated at first glance. But the investigator Lika Besedina discovers common details in the crimes, after which they are combined into one case, and now Lika will have to investigate. Checking her version of the possible location of the next murder, Besedina finds herself on the territory of an abandoned skyscraper. Three months later, she wakes up in the hospital. Because of the trauma, her brain daily resets the information received during the day. Every day, Lika tries to go through this path to the end: remember who she is, reload all the information about the series of murders into her head and have time to figure out the criminal before midnight. Every day she gets closer to the solution, but the night erases in her memory everything that she understood the day before. One day, Lika realizes who the killer is, and realizes with horror that in the morning she will forget about it.