The book by Moscow historian Alexander Radevich Andreev for the first time tells in detail about the Ukrainian characterists, masters of combat in any position and situation, who made up the personal guard of Bogdan Khmelnitsky. Some researchers believe that kharacterniki were invented by some Ukrainian fiction writers, but this is not true. The harakterniki were in the Zaporozhye Sich from the very beginning and, although, of course, they did not catch bullets fired at them with their teeth, the arrows sent at them could be intercepted with both hands, one after another. The reader, together with the author, sees how Bogdan Khmelnitsky and his harakterniki fight off the most dangerous ambushes of the Polish gentry, and how, in the most difficult conditions, the heroes of the Ukrainian revolution won the most desperate battles at Korsun, Pilyavtsy and Batoga. It tells in detail, using all the documents available to historians, about the training of the Ukrainian characterniks, these famous “Ukrainian ninjas” of the Middle Ages. At the end of 2014, a new work by Alexander Andreev, “Ukrainian Cossacks at home, in Europe and at sea,” will be published, the main characters of which will be Ukrainian characteristics.