Ten-year-old Ben Tennyson, his ten-year-old first cousin Gwen, and their paternal Grandpa Max start a summer camping trip across the United States. Ben and Gwen don't like each other's company and start fighting from the moment they set off. At a stop at night, Ben wanders into the woods to cool off and is almost crushed when a meteorite crash lands in front of him. Upon examining it, he discovers it is an alien cargo pod housing a mysterious, watch-like device called the Omnitrix.