Siblings Mimi and Luke unwittingly resurrect an ancient alien overlord who's been entombed beneath their backyard. The creature longs to destroy the universe, but thanks to their possession of a magical amulet, the kids force it to be their new best friend. As the monster reluctantly obeys their childish whims, his magical powers draw the attention of interstellar friends and fiends from across the cosmos. Soon, a rogues' gallery of galactic combatants converge on the strange realm of small-town suburbia and an absurdist battle of Saturday Morning Television-inspired action, outrageous comedy, and freaky comic-book violence ensues—one that will decide the fate of the entire galaxy!