The Consuming Fire by John Scalzi
In this entertaining, fast-paced science fiction novel, Emperox Grayland II, aka Cardenia, pulls out all the stops to keep her empire from unraveling into chaos while also avoiding assassination attempts. The Flow streams (interstellar expressways) begin collapsing, disrupting commerce and travel. Lady Kiva Lagos, sexy and snarky, has become the administrator for a corrupt family corporation, and supports the Emperox. Meanwhile, physicist Lord Marce travels to a star system last visited 800 years ago, finding surviving colonists and an ancient avatar who may help save the day. Dramatic, engaging and action-packed, this sequel to The Collapsing Empire is a fun, fast read.