A messenger from Seer Windlow comes to share the information that Himaggery has disappeared while investigating ancient ruins and legends, and no one has been able to find him for seven years. Mavin sets out to find him, and along the way confronts old enemies, allies with old and new friends, and leaps evil wizards in a single bound.
Ultimately, she rescues Himaggery and they live together for a time. Mavin discovers that they are two utterly different types of people, and her free spirit won't allow her to stay with him. She is pregnant with his child, and leaves him without ever telling him about this or why she is leaving. I hate this kind of stuff. Foolish tragedy caused by failure to communicate.
It's been so long since I read the True Game trilogy that I've forgotten whether all this has any bearing on what happens there, but it seems to me that the hero of that trilogy might be Mavin and H's child, fostered out shortly after birth. It would seem to make some sort of sense out of things if that was the case. I'll have to re-read them some day and get back to you.
Anyway the story about Himaggery's rescue mostly seemed like some sort of filler to make everything work out in the end for them to be tragically separated, so I wasn't all that thrilled with this book. If you've been following the series, then you've got to read it for completion, but if you're already bored with things, then don't bother.