The start to an all-new space-opera series by the Hugo Award-winning, NYT bestselling author of Redshirts and Old Mans War

The Flow, an extradimensional field available at certain points in space-time, can take us to other planets throughout the universe.

Riding the Flow, humanity spreads to innumerable worlds. A new empire, the Interdependency, comes to power based on the doctrine that no one human outpost can survive without the others.

But just as a river changes course, the Flow changes as well. In rare cases, entire worlds have been cut off from the rest of humanity. When its discovered that the entire Flow is moving, possibly separating all human worlds from one another forever, three individualsa scientist, a starship captain, and the emperox of the Interdependencymust race against time to discover what can be salvaged from an interstellar empire on the brink of collapse.