The life of Sophia Kazimirovna Ostrovskaya (1902-1983) contained a lot: childhood in a wealthy family, study at the Faculty of History of Petrograd University, service as the head of the criminal investigation department of the Murmansk Railway, being under arrest, working as a translator of technical texts, the ambitions of an unrecognized writer, friendly relations with Anna Akhmatova, etc. All this was reflected in the pages of her first published entire diary, which she kept from a young age until the middle of the 20th century. A special place is occupied in her records by the blockade of Leningrad, shown in detail and expressively. Only Ostrovskaya's activities as an agent of the special services, in particular to monitor Akhmatova, remained outside the diary.