Secrets is the thirteenth episode of Ben 10, and the last episode of the first season.
With his wounds finally healed, Vilgax decides to personally retrieve the Omnitrix. He again contacts Ben in a dream, which Ben tells Max about. Worried, Max plots a course to Mount Rushmore. Ben ignores Max's warnings not to go alien and flies off to stop trouble along the way, only to engage in combat with Vilgax. After a futile struggle, Vilgax captures Ben and brings him aboard his ship. Having retrieved weapons from a secret base in Mount Rushmore, Max and Gwen free Ben from Vilgax's extraction device. Ben and Vilgax fight again, but Ben surrenders when Vilgax holds Max and Gwen hostage. Unknown to either of them, Max had activated a self-destruct command on Vilgax's ship. Ben traps Vilgax and escapes, leaving his opponent in the resulting explosion.
- Upgrade 2x
- Heatblast 2x
- XLR8 2x
- Diamondhead 3x
- Wildmutt 2x
- Ghostfreak 2x
- Grey Matter
- The Trios Thirteenth stop is Mount Rushmore.
- All 10 aliens were used in this episode
- This is the first time an alien transformation is seen without the normal transformation sequence and is done while moving (as Ben was running when he pressed the Omnitrix)