I love the original Star Trek series and have followed ST in some of its various incarnations over the years and own a pile of tie-in novels. If you're not familiar with Star Trek, the security guards had red shirts as part of their uniforms and they had an appallingly high death rate on away missions. This books is not set in the ST universe but was inspired by it. It's sometimes funny, sometimes clever, often meta, occasionally boring (I dozed off several times). The reasoning, and story line, is sometimes circular, occasionally inspired, occasionally irritating. There's a lot of dialogue and exposition but not a lot of action and our characters, Dahl, Duvall, etc., mostly tumble along. They do some inquiring but mostly are spoon fed the answers by other characters. 
 The main part of the book ends at 68% in the audiobook, followed by 3 codas. Those codas make up approximately 1/3 of the book. The first coda, though too long, was clever and funny, and philosophical. The other codas just weren't necessary and were much too long. 
 Overall, it was okay but I'm in no rush to read more by Scalzi.