River Chronos

River Chronos is a series by Kir Bulychev about Alternate History. The heroes want to change history, so for each event, they Time Travel into an Alternate Universe. They manage to save the Tsar from assassination, develop the atomic bomb ten years early, and resurrect Lenin. There are many Detective Drama elements.

Books in the series
 * The Successor
 * The Storm ff Dulber
 * Return from Trebizond
 * Assassination
 * Reserve for Academics
 * Baby Frey
 * Sleep My Beauty
 * They Do Not Kill Them There
 * House in London