15 year old Ben Tennyson must utilize the Omnitrix yet again in order to locate his missing Grandpa Max, along with his cousin Gwen and former enemy Kevin 11.

整个故事的主角本•坦尼森现在除了使用阿兹米斯给他的新Omnitrix继续保护世界，还遇到新的伙伴入克。格温和凯文因为要去上大学，所以离开贝尔市。这也让本必须面对没有这两位老战友一起战斗的局面。幸好他还有一位新的伙伴战友鲁克。另外…