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Chief Anderson has called an emergency meeting with G-Force at Camp Parker. While Mark is flying there, Colonel Cronus of Earth’s sister planet Riga, flies up beside Mark before playfully zooming off. Mark wonders why he's so far from home.

Once at Camp Parker, Anderson tells Mark Cronus requested clearance to come to Earth, but the clearance was denied. Anderson is concerned it could possibly be Zoltar posing as Cronus as he has done in the past. Anderson reveals a new spacecraft, the FY-9, will be delivered to Riga and the Phoenix will escort it. But no one knows the pilots of the FY-9 have already been replaced by Spectra agents.

En route to Riga, 7-Zark-7 notices the FY-9 change course to head for Spectra. He is unable to reach the Phoenix to warn G-Force because their radio contact has been jammed. No one realizes they have changed course. Suddenly, a squadron of Riga fighters attacks the new ship, just before the FY-9 pilots fire a rocket at the Phoenix.

Mark heads out in his jet to see what's going on. As he launches, one of the Riga fighters secretly fires a time bomb missile into the undercarriage of the FY-9, then the Riga fighters take off. Jason calls Mark to let him know no one on the FY-9 is responding, their communication lines to 7-Zark-7 are being blocked and that they're not above Riga. Mark tells Jason and the rest of the team to stick with the FY-9 while he goes after Cronus solo.

The flight takes them to Omeg II, a primitive, uninhabited planet under Spectra's control in the Crab Nebulae. The pilots land the FY-9 in a base housed inside a volcano. Tiny is worried the Spectrans know G-Force is onto them and Jason orders him to pull away. But the Phoenix is under the control of a traction beam and G-Force's mighty ship quickly loses power and is pulled into the base. By the time the ships land inside the base, G-Force has been knocked out by a pink gas inside their control room on the Phoenix.

Meanwhile, Cronus breaks off from his group and lands his jet on a nearby field. Mark follows and lands right behind him. When Cronus steps out of his jet, Mark demands an explanation and charges him. Cronus sidesteps his attack easily and goes on to explain Spectra agents hijacked the FY-9. He also tells Mark about time bomb that they shot into it. Cronus says they would rather lose the new plane than to have it fall into Zoltar's hands. Mark knows he has to get G-Force out of the volcano base before everything blows up.

When he and Cronus get to the base they find the rest of G-Force has been taken captive. The two quickly free the team and rush to the Phoenix, barely escaping before the missile detonates and destroys the FY-9 and Spectra's base.

Planet Riga is Earth's sister planet

The real Colonel Cronus appears for the first time, and Chief Anderson references Zoltar's earlier impersonation of him

Zoltar awards medals and promotions for his mens' accomplishments

7-Zark-7 can blush

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