Eva Nine, a curious and intelligent teenage girl, has spent her entire life underground, raised by a robot caretaker named Muthr (Multi Utility Task Help Robot 06) in a high-tech sanctuary, Sanctuary 573. One night, Eva sneaks through a mysterious door in the restricted area, emerging into a strange and unfamiliar surface world filled with bizarre creatures and unknown dangers and a strange note titled WondLa. She finds someone to help her, but it's actually an unknown intruder that attacks the Sanctuary. Eva and Muthr are forced to escape but something captures Muthr. Eva is separated from her, emerges onto the surface and finds herself on the alien planet Orbona.