The spirit of romance and wanderlust, which once drove the Petrograd engineer Mstislav Sergeevich Los on an interplanetary journey to Mars, transports Taras Zhdanov and Nastya Belaya to one of the invariants of the Metaverse, in other words, to one of the Branches of the Tree of Times, the parameters of reality of which coincide with described at the beginning of the 20th century by Alexei Tolstoy in the novel 'Aelita'. For young people, the search for the heroes of their favorite book turns from a risky adventure into a serious investigation. The Artifact found on Mars, if not neutralized, is capable of destroying not only the Solar System, but the entire Branch. However, there are those who are interested in activating this attribute of the Metagalactic Game. Aelita's homeland becomes a battlefield for the future of the Children of Heaven.