Blarg! I am fatally annoyed that this book had actual aliens and did almost nothing with them for the entirety of the book. I was very excited for a first contact story, and to go deeper into Jenny's relationships (any of of them), but instead what I got was a sort of political thriller that mostly focused on new or minor characters from the other books in the trilogy. There's still some very interesting ideas in here - particularly about various forms of AI - but overall: ho hum.
Let's see if I can remember the story, which honestly I started skimming toward the end: it's nine months down the line from the end of the last book, and everyone is still recovering from the bombing of Toronto, which killed nearly everyone in the vicinity and threw the planet into (more of a) global climate emergency. Jenny and her crew - Gabe, his surviving daughter Genie, and Elspeth - are up on the Calgary, staring two alien ships in the face, which they refer to as "the birdcage" and "the ship tree." There are some new scientists coming aboard to try and learn how to talk to these aliens - Jeremy and Leslie - one of whom (Leslie) has (I believe) Aboriginal background.
Meanwhile, the Richard Feynman AI has created a "worldwire" which allows "him" to monitor and try and repair the Earth. Not everyone is A-OK with this; in fact, the Chinese see it as a sort of biological attack. Constance Riel of Canadian government and General Valens (Canadian military) are on Earth trying to diplomatically address this; it becomes a big thing that the UN must address, and Jenny gets pulled into it all, having to testify. I guess the main questions are: will they be able to communicate with the aliens; are the aliens there to help; and will they answer those first two questions before human political squabbles turn into outright war.
By FAR the narrative spends the most time on the third of these. It wasn't really what I wanted to read. And Bear still has the habit of writing AROUND the most interesting action, trusting that you will fill in the blanks. It allows her to move through a metric ton of plot quickly, but what if we want to see some of those moments? Thus I felt quite emotionally removed from everything that was happening.
There's an action-y climax, but for me it was too little, too late. This third and final book in the trilogy does wrap up the questions of this book and the series, but for me it leaned too far into debating ideas and politics at the expense of authentic character moments. And it kinda bored me.