And Then There Were 10

Ben Tennyson is a 10-year-old boy from Bellwood. He and his twin cousin Gwen are going on a summer vacation across the country with their grandfather Max in his RV.
Max tries to cheer up his grandchildren with camp activities, but none are motivated. Ben goes for a walk in the woods.
In space, Vilgax is aboard the Chimerian Hammer chasing a small ship carrying a strange device: the Omnitrix.

The ships are damaged and the Omnitrix is dropped from the ship in a pod that falls to Earth.

Ben finds himself very close to the crash site. He approaches the pod and the Omnitrix attaches itself to his left wrist.

He tries to remove it, but it accidentally turns into a creature that sets the forest on fire. Max and Gwen notice the smoke from their campsite and try to put out the flames with fire extinguishers.
Max leaves to find answers at the crash site, warning his grandson not to mess with the watch.
Recovering from his injuries, Vilgax sends a drone to the crash site to find the bracelet.
A camp of vacationers is attacked by the drone. Ben then tries to fight it by transforming himself into another creature.

Next episode

S01E02 - Washington B.C.