The Collapsing Empire by John Scalzi. Tor, 2017. 9780765388889.
Scalzi’s best science fiction novels are a perfect combination of concept, setting, and characters. Reading them is effortless and fun, and it feels inevitable because they’re impossible to put down. This is one of his best.
Somewhere near our universe is the Flow, an extradimensional “river” that allows one-way, faster-than-light travel between some star systems and defines the trade routes that tie humanity’s interstellar empire together. But access to it is about to disappear. Most of humanity’s outposts will die because of their interdependence.
The new Emperox knows the truth — her father hid and supported a scientist who was secretly studying changes to the Flow — but she’s not only new to the her post, she’s unprepared for its politics and power struggles, and her capital is under attack by terrorists. That scientist lives on the empire’s farthest outpost, End. Because of an open rebellion there, as well as the political machinations of an ambitious family (who also seem to know what’s about to happen to the Flow, and are using it for their own ends), the Emperox may not get the proof she needs to convince humanity’s leaders to accept the truth about the Flow before it’s too late.
Throw in one badass ex soldier (the Scientist’s daughter) and a foul-mouthed woman as determined to get laid as she is to make money for her family on a trade run, and it’s super entertaining.