In the constellation of Eridanus there lurks a cosmic mystery. It's as if something has taken a huge bite out of the universe, leaving a super-void. What could be the culprit? A super massive black hole? Another, bigger universe? Or an expanding vacuum bubble, destined to envelop and annihilate everything in existence? Scientists now understand the history of our universe better than the history of our own planet, but they continue to uncover startling new riddles - the hole in the universe being just one. Physicist Paul Davies walks us through the puzzles and paradoxes that have preoccupied cosmologists from ancient Greece to the present day. Laying bare the audacious research that has led us to mind-bending solutions, Davies reveals how we might begin to approach the greatest outstanding enigmas of all.