The collection, dedicated to the 100th anniversary of the Cheka-KGB-FSB, includes articles, historical stories and archival documents that reflect the main stages of the formation and development of state security agencies from 1917 to 2017. This book presents the works of twenty authors, which are based on historical documents and facts of the invisible front of domestic intelligence services to protect the national interests of Russia. The book is intended for a wide audience, students, as well as professionals - historians, political scientists, politicians, and all those who The history of state security of our country is not indifferent.