Even though the series is about space travel in the future, this story is less science fiction and more about protocols, oaths, adhering to rule, and when to take the rules into your own hands. Underneath this all is a Mars separating from Earth plot that feels like the North and South during the Civil War. If science fiction is not your favorite type of story I would still suggest reading this book, because the political and moral compass of people is the main plot of the story.