Alex Guerrero and Teri Culpepper had nothing in common.
He was an elite warrior, trained to be a leader in Earth's premier fighting force.
She was an academic, a professor of botanical sciences, struggling to keep enough grants coming in to support her meager research.
But now circumstances have forced them together, the lives of eight people hanging on the success of their daring mission into unexplored territory on an unknown planet.
Can they work together to find the secret to survival on this alien world, or will their rivalry doom the entire expedition?