A recent battle with Dr. Animo has set off the Omnitrix's self-destruct sequence. Now Ben must travel through the galaxy to find the creator of the Omnitrix, the only one who can stop it from destructing.

The Tennysons arrive back home, but Ben seems to find it hard to re-adjust his lifestyle as a regular old kid again... But before he can do that, villains come and take over his hometown, and it is up to him to go hero before anyone is harmed. And how does the Omnitrix, an alien named Eon, and the Plumbers fit into all of this?