My son and I listened to this one and off for about two months on Audible. It was fine, not among my favorite Scalzi but perfectly enjoyable. The story is about a human colony that is at risk from the "Conclave," an association of alien races that intend to destroy any new colonies in an effort to keep space more peaceful. A number of twists and turns follow along with humorous banter and a deep sympathy for humanity. Its is the third in the Old Man's War series and fits in perfectly well with the previous but didn't "need" to be written, likely more add on to a series than a fully integrated whole.