While transporting Chief Anderson to his mountain retreat, Jason’s vehicle is attacked by a mysterious female driver in a blue mask. After she forces them off a bridge into a body of water, she throws a rose-shaped bomb after them. But Jason is able to convert his car into a sub and escape. When Zoltar’s sister Mala later learns her Galaxy Girl has failed to dispose of Jason and Chief Anderson, she decides to take care of things herself.

At his mountain retreat, Chief Anderson informs G-Force that Zoltar has threatened to blow up the Solar Express – the first monorail to circle the globe – on its maiden voyage. To guard the train, Chief Anderson and Mark will ride on it while Princess, Tiny and Keyop cover them in the Phoenix from above. Jason has gone elsewhere and is unable to deploy with the rest of the team, but when he returns, he figures they have headed for the Solar Express, so he sets off for it as well.

Posing as a public relations rep, Mala greets Chief Anderson and Mark as they board the train. Anderson and Mala talk as their voyage begins, and while he enjoys her company Mark has an odd feeling about her – something familiar. Later, while alone, Mark notices some odd rocket cars out the window of the train, but before he can warn anyone, Mala knocks him out with the butt of her gun. Fortunately, 7-Zark-7 is able to awaken him quickly via his wrist communicator. Mark confronts Mala and she reveals herself to be Zoltar’s sister. She then detaches the rest of the train from the main car, as her Galaxy Girls blow up a bridge and leave the rest of the cars behind.

As Mala boasts to Chief Anderson, the train goes through a tunnel and the lights go out. When they come back on, Mark is sitting in the car! He battles Mala and Spectra soldiers in the car, while 7-Zark-7 has Princess take out some of the other Galaxy Girls outside in their vehicles. But her fight destroys an upcoming bridge and there's no way to stop the train. Mala escapes in her ship, while the train hurtles off the ruined bridge with Chief Anderson still on board. Fortunately, Tiny is able to rescue him. Although there has been a lot of destruction, Spectra has been driven away and Mark says everything can be rebuilt and replaced.

7-Zark-7 doesn't like to admit his own weakness

Zoltar has a sister named Mala

1-Rover-1 thinks Princess is the best looking girl in the Solar System

Note: According to scripts, Mala's last name is spelled Latroz, an anagram of Zoltar

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