Lois Lane is kidnapped and rescued by the teenaged Supergirl. Then, her cousin Superman shows up. Kara is a rebellious teenager and it's only been a few months, from her perspective, that's she's been on Earth. She was sent from Krypton before him, but he arrived quicker because of a Wormhole. Lois and Clark are dating and she knows his real identity. One of the news office workers things he's gay and she's upset with him because he's overprotective. Their arguing is interrupted when something from outer space lands in Arizona. It's a sinister looking robot. After Superman defeats it and takes it back to his Fortress of Solitute Kara recognizes it as one of the robots that attacked the capitol city of Kandor--and that the being responsible is called Brainiac. Kara's afraid this attack will happen again...
In this latest animated movie, everything is sped up and condensed than as portrayed in earlier (90's version) versions of Superman, which is okay, but I thought it a little redundant to have yet another Brainiac story when he isn't all that interesting to begin with.