Archeologist Aczel (Fermat's Last Theorem, The Jesuit and the Skull, etc.) has visited most of the Paleolithic caves still open to the public, and spent years researching European cave art, attempting to explain ""the appearance, around 32,000 years ago, of magnificent paintings, drawings and engravings... inside almost inaccessible recesses of large Ice-Age caverns."" First discovered in the 1870s, these caves were adorned by stone-age forebears over a 20,000-year period. Most of the paintings can be be found only after crawling for miles to where open ""galleries"" are decorated, wall and ceiling, with animal groups rendered in naturalistic detail. Groupings retain similar features in different locations over the whole 20,000 year period, and experts still argue over its meaning: Who were the artists? Why did they hide their art? Did it play a part in mystical ceremonies? Did they appreciate its beauty? Aczel's archeological exploration, including stories about the explorers and scientists who first discovered the ancient artwork, is a lively journey through time into the mystery of a people who may have ""possessed deep understanding and perhaps even a cosmic picture of nature.""