Keys to Death (2002)

Original title: Ключи от смерти

Private detective Stas Severin receives a task from his old friend - to find the murderer of his wife. From the incoherent explanations of the client, Stas understands that we are talking about a large inheritance of the famous antique collector Arefyev, the applicants for which make up the circle of suspects. The mysterious key given to the detective should help in solving the mystery.