Inspired by scientific theories about human history and evolution, this fascinating History Channel docudrama imagines what it would have been like if humankind's most likely ancestors, the Cro-Magnons, had lived side-by-side with the Neanderthals. While Cro-Magnons are smarter and more creative, Neanderthals are certainly stronger -- and their differences add up to a dramatic clash of brains vs. brawn.