Space travel and the ability to colonise Mars has opened new opportunities. But for some it is an opportunity to die. A killing at an outpost of the developing exploration of Mars brings Police Investigator Peter Dunn to the planet surface. There he meets cynical doctor Sarah Mazer, who is concealing the details. The more Dunn studies the facts surrounding the death, the more it leads away from a simple manslaughter and instead to the interstellar TransMat Corporation, who will protect their secrets at any price.