For decades, mankind has been at war with an enemy that resembles the human race so closely that they are known as the Sims. Both sides battle for control of habitable planets across the galaxies, making this a limited war in some respects. Enter Lieutenant Jander Mortas, new to the war zone but eager to prove himself. There's just one problem: Something happened to the ship transporting him to his first assignment, and he awakes to find himself marooned on a habitable planet that appears deserted. Most of the other passengers died in the crash landing, but he's left with three members of the Human Defense Force: Captain Amelia Trent, a psychoanalyst who is better at treating combat stress than experiencing it. Chartist Gorman, a conscientious objector more concerned with preserving his soul than saving his life. Corporal Cranther, a bitter veteran of a brutal slave-scout detachment who values his own skin above everyone else's. Thrown together, they must battle the elements, the enemy, and possibly each other.