Roxanne Trent is a gun runner along with her partner Commander Corliss (Robert Quarry).
Their plan was to use 20th century nerve gas to destroy Earth in revenge for the injuries she sustained in an earlier confrontation and capture of them with Wilma Deering (Erin Gray).
Roxanne sustained these injuries when she fell into the burning cargo hold of her ship, after the illicit weapons she and Commander Corliss were transporting exploded. Roxanne only survived due to Corliss risking his life to pull her to safety. As a result of her injuries, Roxanne possessed a robotic hand of enormous strength.
Wilma attempts to find a way to locate and destroy the nerve gas, which is hidden at the gun runner's hidout inside an asteroid belt. Wilma finds that the only one who has knowledge of how to traverse the belt is Maj. Noah Cooper (Peter Graves). Cooper is an elderly retired leader of the Fighting 69th, who proves he still has it.
Roxanne captured Wilma and Buck. Upon getting reaquainted with Wilma she attempts to crush Wilma's hand until she begins to writhe in agony. The strengtho of her had was shown later when she was able to dent metal when striking it in anger.
Roxanne threatened to burn both Buck and Wilma, so they would know what it was like to be burned. Buck while bound, takes on two guards while Roxanne and Wilma get involved in a cat fight. The fight is stopped when the 69th squadron arrived.
After escaping a cell, Buck and Wilma get involved in a shootout with Roxanne and Corliss. Corliss is injured, and Wilma and Buck are able to escape in a sled before the base was destroyed.
Despite the apparent destruction of their base, Roxanne and Corliss were captured alive, and received medical care from the Earth Defense Directorate.