The Pearsons' summer rental house has it all: plenty of room, a swimming pool and a space alien camping out in the attic. The kids can't help but love the cute little guy, until they learn that he's not alone, and his buddies aren't as nice. Now, what started as a summer retreat has become a brave quest to save the planet. Ashley Tisdale, Kevin Nealon, Doris Roberts and Andy Richter star in this comic family adventure.