In 1962 a Russian space probe accidentally photographs a glass structure on the surface of the Moon.

When the Americans learn of this sighting, C.I.A. agents, Steve Curtis and James Hoffman, are invited to the US Air Force facility known as Area 51.

Arriving in the desert, they meet industrialist, Vigo Saltzman, who allows them to examine a crashed alien spacecraft, which he has had in his possession since 1947.

Saltzman believes the newly discoverered lunar structure holds highly developed alien technology. After the moon landings have taken place, he leads a secret Apollo mission to retrieve these advanced artifacts.

As the Apollo crew speed towards the Moon, Steve Curtis is sent to destroy a rocket which the Russians hope will obliterate the structure before the Americans reach the lunar surface.

Will the Americans reach the structure in time and what revelations does the huge glass dome hold?