Dr. Lauren Wagner is the chief medical officer on the first American mission to Mars. The expedition is a dream come true for her, the fruit of many years of struggle and sacrifice. But this is not mankind's first visit to the red planet: the Russians went ten years ago... and didn't come back. Even more disturbing, the sole orbiting cosmonaut, Carl Bensk – who never even landed on the planet – was also never heard from again. Carl and his companions are presumed dead, but what killed them? Lauren is about to find out...