The Rift is the River Darkness, a starless standing wave of nothingness between galactic arms. A region filled only with visions and voices; innocent terror and mortal atrocity; sacrifice, tragedy, decisions. And heroes.

Set in the same universe as the acclaimed Brightness Falls from the Air, against the backdrop of a far future university library where alien students are researching a project on the history of the human race, acclaimed multiple Hugo and Nebula winner James Tiptree, Jr. weaves a tapestry of individual courage and passion into a saga of exploration, confrontation and crisis--the Federation's conquest of the Galactic Frontier.