Animation technology has grown by ”leaps and bounds” since Tim Johnson codirected the cartoon hit Antz back in 1998. And he wanted to show that change in Home, which he dubs a ”postapocalyptic alien-invasion buddy-comedy road-trip animated movie” about a purple alien (voiced by The Big Bang Theory‘s Jim Parsons) who teams up with a human girl (Rihanna) to save Earth. ”The sci-fi genre can be very narrow and self-imitating and can get stuck in a rut,” says Johnson, who was already a fan of the movie’s source material, Adam Rex’s children’s book The True Meaning of Smekday (a favorite of his young sons). ”I wanted to design an alien technology that was really unexpected,” he says. So Home‘s extraterrestrials have the ability not only to completely turn off Earth’s gravity but also to shoot bubbles instead of laser beams.