The book “Microbes from Hell” is both an historical report of the discovery of hyperthermophiles and a personal recollection by the author of his own work on these microorganisms. The molecular mechanisms allowing these bugs to thrive at temperatures above 80°C, up to 110°C are described, with some emphasis on the problem of DNA stability and the mysterious role of reverse gyrase, the only protein specific of hyperthermophiles. The book includes stories depicting science in action, including a submarine trip to collect samples in deep-sea hydrothermal vents. Most hyperthermophiles belong to archaea, one of the three domains of life. The discoveries of archaea by American molecular biologist Carl Woese, and of their unusual viruses by German microbiologists Wolfram Zillig and David Prangishvili are discussed in some details. A large part of the book deals with controversies about the place of hyperthermophiles and viruses in the history of life: did life originated or not at high temperature? Are hyperthermophiles relics of primordial life or marvels of adaptation? What is the nature of viruses? The author’s work on archaea led to the discovery of the protein that initiates meiotic recombination in eukaryotes. Many other discoveries testify for a close evolutionary relationship between archaea and us. In the last chapter, the present controversies about the topology of the universal tree of life and the origin of eukaryotes are discussed, with emphasis on recent work in the author’s laboratory supporting the classical Woese’s tree of life.