The Warrior and the Professor — Susan Kelley

Elias, warrior of Gaviron, fights beside and befriends the two Tucker brothers as part of Earth's military. The tide has turned in favor of humanity in their battle against the insect-like raynids. When Earth's leaders decide they must travel to Gaviron and learn the origin of the raynid invasion, Elias finds himself forced to go along and face his nightmares.