The mystery ship came from the great depths of space beyond the solar system!
Commander Eric Mann; Captain Alan Carter; Zarran Commander (aggressive alien); Kull Council speaker (peaceful alien)
The Kull are a peaceful people who have discovered random anti-matter blotches throughout space. To warn travelers of the blotches they station lighthouses in their vicinity. One of the lighthouses drifts into our solar system. Two Earthmen investigate the lighthouse and become prisoners when it is retrieved by the Zarran, enemies of the Kull. The Zarrans rig the lighthouse with crystals to absorb the deadly radiation from the blotches and beam it onto the Kull planet. The Earthmen help the Zarran defeat the effects of the radiation and are rewarded with knowledge to take back to Earth.