From the back cover:
A world to be won ...
Fleet had discovered a new world! It was suitable for terraforming, if harsh; a breakthrough. Experts quickly designed and built the support outpost for Planet Kask Colony. The work was all done robotically.
The support station would support and train thousands of colonists. Exhaustive testing confirmed every feature, and the first shiploads of staff -- mostly trainers and administration -- prepared to move in.
Then communication and telemetry ceased.
Repeated call to the robotic A.I were not answered.
"Fleet, this is Sigma One-Delta ... We have a Problem.
"Kask Support is silent.
"We have a Dark Outpost.