Twila Grimm has lived her whole life inside the sterile limits of the Biodome, an isolated domed oasis in the middle of a ravaged Earth.

The outside is world of mystery and disease: where those infected by the deadly CM virus are sent to die. This is a land of disease and death; of warring tribes and half-crazed factions living on the edge of sanity.

But the outside is also where Twila Grimm's destiny lies. For she is much more than what she appears and the secrets about her own origins may prove to be the world's salvation ... or its ultimate destruction.