20 years ago the Jao conquered Earth in a savage and bloody battle. They are now tyrannical occupiers, claiming they are preparing for attack by the semi-mythical Ekhat. Humans don't believe them. Into this comes newly appointed Subcommandant Aille, who is horrified to learn about the tyrannous rule, and the way it is stopping Jao and humans working together in preparation for the Ekhart. Behind the scenes, shadowy figures scheme for their own ends.
This is a good alien invasion story, with both sides having good guys and bad guys. It's good to have superior aliens (although there are strong indications they aren't all that superior in some ways, and good old Terran know-how will come into its own). They are alien enough to be interestingly different, but not so alien as to be incomprehensible (unlike the bizarre Ekhat!). There's good closure at the end of the book, but there is clearly more to come.
It's two years since the Jao and humans resolved their differences, and started to cooperate in their fight against the Ekhat. Some Jao spaceships have discovered what might be the remnants of a Lleix outpost. The Jao have a guilty conscience about the Lleix, who they hunted to near extermination back when they were still enslaved by the Ekhat. A human-Jao expedition sets off to contact the outpost, but how will they be received?
This is an interesting sequel to the original invasion story, gradually building up a coherent defence against the horrific and incomprehensible Ekhat. Here we get a new alien race. I hope the series continues (and with rather less than seven years until the next one!), as I want to see how all these diverse aliens with their different cultures manage to get on together.