Earth is dying and humanity is running out of time. 12 light years from home, Tau Ceti f offers a small sliver of hope. When the colony ship Cassiopeia crash lands on the planet, its crew soon realize they are far from being alone.

Hunted by an alien organism capable of mimicking its prey, the crew of the Cassiopeia must outwit their pursuers to make it home alive. As they battle to survive, they are confronted with the hardest choice of all: to save themselves, they must risk the lives of everyone on Earth.