There, the aliens adjust to human culture and try to fix their spaceship (as well as to restore their nearly-dead parents King Fialkov and Queen Coranda) to return and take back Akiridion-5, which is being taken over by an evil dictator known as General Val Morando, who has already sent out a team of intergalactic bounty hunters, called the Zeron Brotherhood, to find and catch the alien prince and princess.

[6] After investigating a way to stop Val Morando and find the hiding place of Aja and Krel, Zadra, one of the noble protectors of the royals from Akiridion-5, arrives on Earth.

After successfully defeating him, Aja (now Queen), Vex, Zadra, Luug and the rest finally return home, joined by Eli, who has volunteered to be Earth's ambassador on Akiridion 5.

Princess Aja and Prince Krel also appeared in the Trollhunters episodes "In Good Hands" and "The Eternal Knight, Part 1" in their borrowed human forms.

[7] It has been praised for its depiction of immigration through a sci-fi lens, with Dave Trumbore of Collider writing, "... the subtext here, which is hard to miss even for younger viewers, is that Aja, Krel, and Vex are stand-ins for immigrants, refugees, and "illegal aliens" ... the show is re-examining the actions of the anti-immigrant government agents and the aliens' allies alike.