A girl materializes claiming to be Tenchi's daughter, and the entire cast has to reckon with the possibility that their lives just became irreversibly complicated. Ryoko and Tenchi descend into a demon's realm to fix a wound in the past neither of them created. The movie understands that the Tenchi cast works best when chaos isn't just comedic, it's personal, pulling at the actual relationships that hold the show together.

A teenage girl approaches Tenchi Masaki and calls him Daddy. Assuming she has him confused with someone else, he takes her home, where she introduces herself as Mayuka Masaki, his daughter. The girls of the household doubt her claim until a DNA test confirms Tenchi is her father, and Washu concludes that Mayuka comes from the future as the result of a recent time distortion. Everyone tries to welcome her except Ryoko, who senses something sinister behind Mayuka's charm. Her arrival has consequences reaching into the past that put Tenchi in danger, and he and Ryoko must enter the realm of a demon named Yuzuha to set things right. The film mixes action, comedy and science fiction.