Ben Tennyson is your everyday, average 10-year-old until he discovers a mysterious watch hidden in a meteorite that crashed on Earth. He soon learns that the supernatural watch allows him to transform into 10 different alien beings while keeping his kid personality. As he morphs into these various creatures, he discovers each alien's unique powers and incredible abilities. Ben's amazing adventures take place over the course of a seemingly endless summer as he travels the country in an RV with his Grandpa Max and 10-year-old cousin Gwen. Gwen and Max know all about Ben's extraterrestrial watch, and they sometimes lend him a hand in his quest to fight wrongdoers and save the world from evil.