Fourth in the Old Man's War series. A young girl who also happens (for reasons to complex to get into) to be a sort of goddess/mascot for a race of aliens, is part of a group of people colonizing a new planet. It doesn't take long until the colony is threatened by unknown predators--and their planet is used as a pawn in intergalactic war. Our heroine, no wilting violet, plays a vital role in resolving the conflicts and saving her new home. 
 This is great space opera. Scalzi's distinctive sarcastic wit is evident not only in Zoe's 1st-person narration but in a lot of the other characters as well, which reminds me somewhat of Jo Goodman--all the characters are witty in the same way. Fortunately for Scalzi, and this book, it's an appealing narrative voice. Even though it is in a series, this book stands alone perfectly well, and there is no awkward series-related infodump to trip over. 4 stars.