Galiana returns from an exploring trip with a "wolf" in her mind. It's a machine that's part of a machine culture that's been killing every culture that makes it to space. Galiana was once able to get news from the future, so the Conjoiners are getting ready to evacuate out of the galaxy themselves. First, though, they want their hell weapons back from Volyova and Khouri.
When Clavain finds out the Conjoiners are getting out and leaving all the other humans for the wolves, he deserts, gets an army together, steals a lighthugger, and takes off to get the hell weapons himself, to give to humans. Antoinette goes with him.
The machines (more properly called The Inhibitors) are taking the sun apart so it will kill all the planets and people where Volyova and Khouri are, which is why they're trying to evacuate. Everybody comes together in shifting alliances and some make it through.