The article is a publication of and extended commentary on Mikhail Kirillovich Gribovsky’s text. He was in charge of the Guards Corps’ secret military police service organized in the early 1820s, after the “Semenovsky history”. In 1822, he compiled a note which is kept in the Russian State Military History Archive. The commentary describes the prehistory of the creation of the secret police: Gribovsky’s activities, his brochure On the State of Landlords’ Peasants in Russia and its perception by contemporaries. The article provides general information about the service created by Gribovsky and peculiarities of its financing. It refers to Gribovsky’s note on the Decembrist Union of Prosperity (thanks to it Alexander I had information about this society) and his three more notes, published in the last decades. The author concludes that Gribovsky writes in his note about the attempts to find the Brief Instructions to Russian Knights by M.A. Dmitriev-Mamonov, which were published in 1816 in limited edition and have not been preserved. He gives a brief history of the organization, the Order of Russian Knights, for which this brochure was compiled, and implies that this Order did not exist. Celebrities involved in the project of the Order of Russian Knights are listed. Despite the fact that the note is not signed, the author attributes it to Gribovsky on the basis of handwriting analysis and identifies the likely person behind the abbreviation. The note shows how political police worked in Russia at the end of Alexander I’s reign. For example, the Gribovsky’s interest in the Order of Russian Knights was caused by the assumption that M.A. Dmitriev-Mamonov’s Brief Instructions to Russian Knights were, in fact, a charter of the Union of Prosperity.