This study of E. Tolstoy “The Keys of Happiness” is dedicated to the little-known early period of the creative biography of Alexei Nikolaevich Tolstoy, which had a profound influence on all of his subsequent work. These are the years spent in Paris and St. Petersburg, in communication with Gumilev, Voloshin, Kuzmin, this is participation in Meyerhold’s theatrical experiments, in the Apollo magazine, in the work of the artistic cabaret “Stray Dog”. The book also examines plots and situations related to Tolstoy’s wife in 1907–1914, the avant-garde artist Sofia Dymshits. The author introduces into scientific use a whole series of unknown handwritten materials and recordings of oral conversations. Elena D. Tolstaya is a professor at the University of Jerusalem, the author of monographs on Chekhov, “The Poetics of Irritation” (1994, 2002) and Alexei Tolstoy, “Tar or Honey: Alexei Tolstoy as an Unknown writer. 1917–1923" (2006), as well as the collection "The World after the End. Works on Russian literature of the 20th century", including a series of her articles about Andrei Platonov.