The film intertwines the intrigues at the court of Peter III and the mysterious murders of our days that happened on the territory of the Oranienbaum Museum-Reserve. At one time, the estate was donated to Menshikov and named Oranienbaum in honor of an orange tree. According to legend, Peter I came across a greenhouse with a wonderful "orange tree" in a tub on the territory of the estate and laughed after reading the sign Oranienbaum. The estate inherited later by Peter III was completed, and under Catherine the Great a Chinese palace of amazing beauty appeared in it.