In one of the courtyards of Vasilievsky Island, in the ancient Quarter of German pharmacists, there is a strange brick tower, shrouded in an aura of frightening mystery and containing many unsolved secrets. Several centuries ago, in this place there was a laboratory of the pharmacist Wilhelm Pehl, who was obsessed with finding the elixir of eternal life and invented a formula for making wishes come true. Until now, no one can find the entrance to his secret laboratory, carefully guarded, as legend says, from prying eyes by formidable winged monsters - griffins. During the day they hide in the tower, and at midnight they fly out and terrify the residents of the quarter. Nowadays, amateur detective Nadezhda Lebedeva, investigating the mysterious death of an ordinary architect, manages to lift the veil of mystery about the Griffin Tower...