Who would put a ceiling on humanity's expansion into space?
That's what Gus Grissom wants to know. While fishing offshore from Cape Canaveral, he glimpses a mysterious undersea city of unearthly geometries, marked with a strange three-armed cross symbol.
His efforts to research it bring him veiled threats from strangers at his door. Trouble blights an exemplary career. However, Gus refuses to be cowed into silence, and pursues every lead he can find.
HP Lovecraft wrote that we live on a placid island of ignorance and were not meant to travel far. This is the Space Race in a world where the Soviet Union is not our only adversary.