Alekseevsky ravelin of the Peter and Paul Fortress is the most mysterious prison of the Russian Empire for the most important state criminals. Neither the ranks of the commandant's department nor those who served in this prison knew about those who were imprisoned within its walls. People came here solely by personal order of the Tsar - and few people left the “Secret House”. The book by Pavel Eliseevich Shchegolev (1877–1931), a historian of literature and social movements, consists of essays from different years dedicated to the prisoners of the Alekseevsky Ravelin. The heroes of the book are Prince S.V. Trubetskoy, N.G. Chernyshevsky, D.V. Karakozov, M.S. Beideman, S.G. Nechaev, M.A. Bakunin.