On Earth, Federation President Nanietta Bacco gathers allies and adversaries to form a desperate last line of defense against an impending Borg invasion. In deep space, Captain Jean-Luc Picard and Captain Ezri Dax join together to cut off the the Collective's route to the Alpha Quadrant. Half a galaxy away, Captain William Riker and the crew of the starship Titan have made contact with the reclusive Caeliar — survivors of a stellar cataclysm that, two hundred years ago, drove fissures through the structure of space and time, creating a loop of inevitability and consigning another captain and crew to a purgatory from which they could never escape. Now the supremely advanced Caeliar will brook no further intrusion upon their isolation, or against the sanctity of their Great Work. … For the small, finite lives of mere mortals carry little weight in the calculations of gods. But even gods may come to understand that they underestimate humans at their peril...