The book, written by the famous French writer Pierre Boulle, includes several action-packed short stories. “The Mysterious Saint” is a dynamic phantasmagoric parable about the terrible, catastrophic events associated with the invasion of the black plague that devastated Europe in the 14th century, which struck down even the unfortunate lepers of the leper colony of Sick Mountain. “The Financier’s Miscalculation” (“Interference”) is a detective story with a love affair. “The Heart and the Galaxy” is a science fiction story about mysterious signals from space that famous scientists are trying to decipher, abandoned on an expedition to the far side of the Moon. In this short story, the author successfully used the techniques of mathematical logic, and did it in such an accessible form that a reader far from the exact sciences will easily and with pleasure discover this aspect of science - the mystery of binary signs.