Nine-year-old Milo (Seth Green, whose voice is altered to sound younger) has a loving but occasionally disciplinarian mom (Joan Cusack) who sends him to bed without a movie because he feeds his broccoli to the cat. In response to her nagging, Milo spits out, "I wish I didn't have a mom," leaving her in tears. That night, an alien ship abducts her, but not before Milo jumps aboard and flies back to Mars as a stowaway. On Mars, Milo evades detection by jumping down a trash chute that leads to an underground Martian garbage dump, where all the male Martians are kept locked away by the ruling females. Milo meets Gribble (Dan Fogler), a tech-savvy human who explains that every 25 years, the Martians abduct a good Earthling mother in order to program a flock of nanny robots who raise Martian girl babies. If Milo can't save his mom before programming, she'll die -- and he'll be stuck on Mars forever.
