A certain Anton Dyagilev turns to Yana and Margosha, co-owners of the detective agency “Two Parrots,” for help. About ten years ago, his ex-wife Nastya went to a monastery under strange—and very mysterious—circumstances. Nastya occasionally writes to her former husband. In one of the letters she says that the abbess of their monastery has been murdered.
Anton reads between the lines and understands that Nastya is very afraid of someone. He begs Yana and Margosha to start their investigation.
A whirlwind of dangerous adventures leads the investigators to uncover a legendary catacomb secret—the last хиротония of the Holy Patriarch Tikhon.