Who was Hermes Trismegistus, regarded by the Greeks and Egyptians as the inventor of language, writing, religion, music, astronomy, and wrestling? Who was Hermes Trismegistus author of the eighteen tractates that came to be called the Corpus Hermeticum as well as the Asclepius and the Kore Kosemue? Who was Hermes Trismegistus, who Cicero called the fifth and final of the five incarnations of the Greek god Hermes and tutored the great Egyptian gods Isis and Osiris; who donned the Helm of Hades, a magical cap of invisibility, to slay the giant Hippolytus during the battle between the titans and the gods and who taught the Egyptians their burial rites. We go in search of the legend, the myth, the sage Hermes “thrice great.”