1The Transmogrification of Eunice
A mysterious alien girl named Eunice has no memory and is being hunted by Sunder. While evading Sunder, Ben soon discovers that Eunice has nature-based abilities.
2Eye of the Beholder
Ben, Julie and the rest of the heroic crew embark on a dangerous journey that could cost them all their lives in an effort to achieve the safe return of Ship and his former owner Baz-L.
3Viktor: The Spoils
The King of Zarkovia asks the team for help with a civil war. The team agrees to help when they find out Dr. Viktor may be involved.
4The Big Story
Jimmy Jones is looking for the biggest new story he and Ben can tackle, but thats when he stumbles upon a strange pink tentacled creature which crashed from the sky into a near by cave.
5Girl Trouble
Gwen is excited by the prospect of her cousin Sunny paying the team a visit while dealing with the Robots of Dimension 12. But her excitement quickly turns into trepidation when it is uncovered that her cousin is not all that she appears and has some particularly sinister intentions.
6Revenge of the Swarm
Victor Validus resurfaces and attacks Ben at night. Elena Validus and the nanochips return.
7The Creature from Beyond
The Forever Knights unleash an evil force mistaken for an ancient weapon.
8Basic Training
Ben, Gwen, and Kevin are summoned to a Plumbers' Academy to go under training that is supervised by Magister Hulka.
9It's Not Easy Being Gwen
Gwen has always been a multi-tasker, trying to juggle school, hobbies, friends and her work as a hero, waking up early and going to sleep late. But Gwen's already packed day is about to get worse when Dr. Animo attacks with an army of giant frogs and Gwen is forced to make a hard choice.
10Ben 10,000 Returns
Following a visit from Paradox after a fight with Eon, Ben 10,000 arrives 20 years from the future to seek the aid of his past counterpart in tracking down Eon.
11Moon Struck
Grandpa Max tells the team about his first UFO encounter, which led him to meet Verdona.
12Prisoner #775 Is Missing
After a base is attacked, Max is infuriated when they learn it was a secret alien prison facility. While Max argues with the officer in charge, the team tries to locate an escaped prisoner.
13The Purge
Old George, the original Forever Knight, reclaims his position, and orders the Knights to remove all aliens on Earth.
14Simian Says
Simian asks the team for help when a DNAlien takes over his home world.
15Greetings from Techadon
Ben faces Tecadon killer robots that have been programmed to kill him. Each robot is more powerful than the last one. Ben's only chance to survive is for Gwen to find out who commissioned the robots.
16The Flame Keeper's Circle
Julie gets Ben to visit a charity organization who wants to improve the world with alien technology. Ben soon discovers the charity's benefactor is an old enemy.
17Double or Nothing
Ben finds out there's a new show called 'Ben 10: Live." He finds an old enemy running the show and cashing in on his fame.
18The Perfect Girlfriend
Julie suddenly leaves a tennis tournament and spends all her time with Ben.
19The Ultimate Sacrifice
Ben's Ultimate transformations have developed their own personalities. Now they want their freedom from Ben.
20The Widening Gyre
Colonel Rozum asks the team to investigate an island of garbage where people have been disappearing.
21The Mother of All Vreedles
Ma Vreedle goes to Earth to expand her family by creating clones and using all the water on Earth.
22A Knight to Remember
The Flame Keepers realize their mistake too late. Vilgax wants the power of Daigon. The Forever Knights are out to destroy Daigon. Ben and the team try to sort things out.
23Solitary Alignment
Azmuth reveals the origin of the sword and how he first encountered Old George. Ben comes to a decision on how to handle the Daigon.
24Inspector #13
A Techadon weapon master comes to Earth and wants the Ultimatrix.
25The Enemy of My Frenemy
Gwen and co revisit Legerdomain in hopes of rescuing Charmcaster.
26Couples Retreat
After Darkstar opens the Door to Anywhere, Charmcaster comes through, and the two team up to give Ben, Gwen, and Kevin the fight of a lifetime.
27Catch a Falling Star
Movie starlet Jennifer Nocturne is recaptured by the evil Captain Nemesis!
28The Eggman Cometh
Dr. Animo is unexpectedly paroled from prison and starts up a company selling eggs, which in fact contain mutant dinosaurs which he wishes to distribute around the world.
29Night of the Living Nightmare
Albedo attempts to get the ultimatrix by invading Ben's mind.
30The Beginning of the End
The final battle between the Forever Knights and Dagon's Esoterica is in full swing, with Ben caught in the middle!
31The Ultimate Enemy (1)
Dagon is getting closer and closer to entering our dimension thanks to an old foe.
32The Ultimate Enemy (2)
Vilgax re-emerges in his most powerful form ever! Can Ben stop him and save the universe?