A new federal marshal at a mining colony on Jupiter’s moon Io investigates an apparent suicide and uncovers a drug smuggling ring. Marshal O’Niel confronts Sheppard, the mine manager, for his part in the ring. Several assassins are brought in to murder O’Niel. With the help of the station doctor, O’Niel engages in a desperate shoot-out through the colony.


Based on the Western classic High Noon.