An ancient artifact robs Kevin of his powers, rendering him helpless when Gwen and Ben find themselves in terrible peril. A curious alien box spells trouble for the town of Bellwood. And Gwen travels back in time to right a terrible wrong. It's Season 4 of BEN 10 ALIEN FORCE! The action is intense. The adventures are out of this world. And the shocking showdown between Ben and Vilgax will bring this Season to the most dramatic conclusion ever!