Nadya Mitrofanova, an employee of a historical library, is trying to build a happy life with her former university classmate, now a sought-after and charismatic journalist, Dima, who is far too busy with work. During his business trip, Nadya meets her new, noisy neighbors—aspiring model Lisa and runway star Sonya. The arrogant beauty Sonya shows off a diamond engagement ring but does not reveal her fiancé’s name. The friendlier Lisa invites Nadya to a modeling agency party, where the modest librarian unexpectedly attracts the attention of the agency’s director, Marat. But the party’s main «surprise» is Sonya’s murder: Nadya finds her dead in the dressing room, and the ring is already gone.
