Mike and Ellen are stranded near the peak of a newly erupting volcano along with Anton who is severely injured and cannot be moved. Their exploration vehicle is disabled and dangerously overheating. Isoke has gone on foot for help, but the air and fuel he can carry may not be enough to get him within range of a support team, nor in time to help his friends. The forces of a native army continue their advance in their quest for territory. Venture's rival group on Earth has extended their reach to two other worlds, leaving the Venture project uncertain whom to trust and pressing for intervention by the courts to avert a planetary disaster.