Hancock's thesis is based on the discredited, controversial, and refuted
Younger Dryas impact hypothesis, which proposes that the
Younger Dryas climate event was caused by one or more large comets striking the Earth around 10,800 BC. Hancock argues that this caused widespread destruction, with a short-term return to
Ice Age conditions followed by massive flooding that altered the continental landscape. Specifically, he claims that coastal civilisations in and around the Atlantic Ocean, Southeast Asia and the Pacific Ocean were destroyed by
rising sea levels. He argues that this was the origin of various
flood myths around the world, and that "what we think of as human history is merely the record of human events that have transpired since the last, great planetary catastrophe." To support his theory, Hancock discusses archaeological sites such as
Göbekli Tepe in Turkey, the
Roman Heliopolis in Lebanon, and the
Egyptian pyramids. He claims that parts of these sites were built more than 10,000 years ago, in some cases much earlier than accepted by orthodox history, and with techniques and technology that were not yet supposed to be in existence. He therefore supposes that they were constructed by theorized civilisations destroyed by the Younger Dryas impact event, or else the survivors of the event and their immediate descendants. In the later case, he proposes that their purpose was to pass on the knowledge of these pre-cataclysm civilisations, with their builders being the book's titular "magicians of the gods". ==Reception==