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At the beginning of her reign, she encounters Xaviar a rogue Galactican who convinces her that he is a god, as proven by his "flying chariot" and ability to render himself invisible. To allay the fears of her high priests, she poisons Xaviar's drink to prove that Xaviar is a god. Since this is not true, this leads to his fearful flight to the Earth of 1980 AD, where she is taken out of her time as she fears that Xaviar will not return to her, believing him displeased with her for doubting his claim of being a god.
As Troy and Hamilton bring Xaviar to be treated by Hamilton's old school friend, Dr. David Rubin, Dillon is tasked to bring Cleopatra back to her time frame. At Xaviar's previous direction, she evades Dillon and arranges transportation to the Museum of History, where Xaviar will later meet up with her after being treated.
Dillon pursues her to the Museum of History, where Cleopatra later discovers via an exhibit that she will marry Julius Caesar in 46 BC and that she will rule Egypt until her death by the bite of an asp. When she avoids Dillon yet again, thanks to the assistance of Williams' guards at the museum, Williams attempts to solicit her assistance in finding her own tomb, rightfully believing that she deciphered the hieroglyphs, although oblivious to the fact that he is talking to Cleopatra.
On Galactica, Dr. Zee's computers inform the Galacticans that if Cleopatra is not returned to her time period, Egypt will prematurely fall to an unknown Earth-based power resulting in a chain of events that would delay the discovery of North America by 100 years.
Xaviar, however, returns Cleopatra to her own time, but does not rule by her side. Once Xaviar plays his hand, Cleopatra realizes that he is no god, and is stunned by Xavair's laser pistol after Dillon, Troy, and Hamilton confront him in Cleopatra's palace in 48 BC. When she awakens, she relays to her high priests that she had a "strange dream" as she recovers from her stun-induced headache (The Day They Kidnapped Cleopatra, unproduced script)