In this science fiction novel, a parallel universe is the backdrop for an extraordinary encounter between two different versions of humanity. The story unfolds as a Neanderthal physicist accidentally crosses over from his Earth, where Neanderthals became the dominant intelligent species, into our world, where Homo sapiens prevail. The narrative explores the resulting cultural shock, ethical dilemmas, and intellectual exchanges from this cross-dimensional meeting, while also delving into the contrasting societal structures, technologies, and philosophies of the two distinct human civilizations. The book challenges readers to reflect on what it means to be human and the paths not taken in our own evolutionary history.

The 10593rd greatest book of all time