Tim O'Connor stars as Major Clint Anderson, who is a part of a lunar expedition exploring the moon's surface who accidentally discovers a large spherical object they call a moonstone. Alex Nicol plays General Lee Stocker, who is at odds with Anderson over an old grudge, while Ruth Roman stars as Professor Diana Brice, who is involved with Stocker. The whole crew will soon become involved in an intergalactic conflict when intelligent life forms from the planet Grippia are discovered inside, refugees from their tyrannical leaders who have learned about their discovery, and are on the way to get them, unless the humans can find a way to help... Good premise and some atmosphere, though marred by mundane human drama.