Zoe and her crew are hunted through the bowels of Mars Base Bowie by a horrific creature that knows only hunger. The monster picks them off one by one like it were wolf thinning a herd of helpless cattle. After a day of wandering, sleep deprivation and huger pains begin to sow dissent within the ranks. The crew turn on one another with the same familiar savagery as the hostile alien that peruses them. Lines are drawn and loyalties are tested; as the astronauts race for their lives.