34497a3fe0ef52949a1ba8e99894ed69 This article belongs to the Classic Continuity
This article is about the episode. You might have been looking for Professor Paradox.

Paradox is the twelfth episode of Ben 10: Alien Force.


50 Years Ago

It is the 1950's. A man and his assistant are trying a time experiment using a large round portal containing Quartz crystals, as officials of the US Army watch. Unfortunately the experiment fails, causing the man to be sucked up into the portal, while an unseen creature, whose shadow is only visible, is heard growling.


Ben, Gwen and Kevin visit Los Soledad after hearing of a disturbance. The place is wrecked and they see materials partially sucked up in an old machine and fossilized animal skeletons. There are also trails seemingly burned into the ground and through walls. Suddenly, a creature arrives and Ben turns into Chromastone to fight it.

2011-10-24 2101

The Trans-Dimensional Monster

The creature gets away and Chromastone transforms back into Ben. The team enter a lab (which is where the time experiment took place) and find the remains of the portal. Then, a mysterious man appears and Ben turns into Swampfire. The man offers Swampfire a gumball. He then disappears and reappears outside. The trio follow him, but before they can question him, the creature reappears and Kevin tries to fight it, but strangely, punching it changes him into an old man. The unknown man flees to draw the creature away.

Kevin begins acting like an old man and Ben tries driving Kevin's car to try and find help. The creature appears again and chases them, ageing Kevin's car to a rusted broken state. They eventually escape the creature and meet the strange man again, who changes Kevin back to his proper age. However, he says regressing a car is beyond his ability. Ben asks the man who he is, and the man explains back in the 50's, he was involved in an experiment involving time-travel.

The man was sucked into the portal and was trapped in the space-time continuum for 100,000 years or more, having not to age, sleep or eat, just exist. He became insane but got bored and decided to learn. He now has a total understand of the space-time continuum, enabling him to travel anywhere and when he wants. Gwen decides to name the man Paradox as he forgot his real name.

Paradox's current concern is the creature they've encountered. The creature came into their plane of reality when his experiment went awry. Gwen points out that this creature couldn't have been around for fifty years, as they would've known about it. Paradox explains that his experiment flung this creature to the present. Ben and the team ask why the creature needs to be stopped if it's only attacking an abandoned military base.

PX (368)

Paradox and the team on the Moon

Paradox then brings them to the Moon (for some reason, with a breathable atmosphere) and shows the team the best possible future if the creature wasn't stopped, Earth turned dark and brown. They then spot a future Paradox who had failed to prevent this catastrophe. The future Paradox urges his counterpart not to repeat his mistakes and sends them back to the present.

Gwen suggests that they simply go back and prevent the time experiment from happening. Paradox says they can't do that because it would also prevent him from becoming a time traveler who has helped the universe hundreds of times. He almost mentions one adventure that he and Ben had in saving the universe. They then spot the creature, so Ben transforms into Jetray and shoots the creature, but the creature was immune to the beams. Paradox throws some gumballs to the creature and momentarily slows it down due to the fact that gumballs can last a long time.

Paradox then grapples with the creature. Though he exists outside of time, he says he can still feel the eons passing. Ben suddenly thinks of something and tells Paradox to take them back to the time of the accident. While Paradox holds off the creature, Ben, Gwen and Kevin head for the lab, where the experiment is about to be carried out. Ben tells Gwen and Kevin that that the creature wasn't acting like an ordinary creature, but someone looking for help. This makes it clear that the creature is actually Paradox's old assistant Hugo, and that he was transformed into an inter-dimensional being as he was also sucked into the time portal as well as Paradox, traveling forward 50 years.

Paradox and Hugo

Hugo and Paradox about to leave

As the experiment begins to fail like before, Ben transforms into Humungousaur (who turns out to be the unseen creature from the beginning of the episode), and saves Hugo, keeping him from getting sucked into the portal. The creature transforms back to Hugo, much to Paradox's realization. Paradox takes the team back to the present, where they meet an older Hugo, who greets Paradox and apologizes about the experiment. Paradox understands and offers Hugo a chance to time travel, before they walk into a portal together to explore time, leaving Ben and his friends seemingly stranded.

As the team are about to leave, Kevin curses Paradox for not changing his car back. But once they reach the exit, they see Kevin's car, brand-new (from 30 years ago according to Kevin), and with a note left by Paradox saying: 'Kevin, try to keep in mind that if this car comes into contact with anything else from 1976, it will explode like anti-matter. Enjoy! -Paradox.' Kevin, Ben and Gwen then drive back home, with Kevin querying if the note was a joke.

Noteworthy Events

Major Events

Character Debuts

Minor Events

  • It is revealed that Kevin used to drag race with some unnamed people at Los Soledad, leaving behind a message "KEVIN RULES!".



Aliens Used



Kevin: You didn't need to come. Gwen and I could've handled this alone. It's nothing really.
Ben: It doesn't sound like nothing. Weird noises, unearthly lights, rumors of weird creatures out here.
Kevin: Yeah, the dudes I heard it from aren't totally reliable~
Gwen: Isn't that like a big bad boy thing to do? Come out here to the ghost town to drag race.
Kevin: How should I know? I just know them from autoshop.
(Gwen and Ben spot graffiti that reads: "Kevin Rules!")

Quotes Right


Ben: Grandpa Max said Los Soledad used to be a big military base back in the 50's; some kind of research facility.
Kevin: Yeah, must've been some serious research. Check out these walls. Fifty years later and there's still no way in. (looks at large holes) No way! These weren't here. Gwen: (referring to holes) Did anyone notice some of them are vaguely person-shaped?
Ben: Weird... Maybe something, I don't know, burned through the walls.
Kevin: Like what?
Ben: The same thing that burned these weird trails everywhere.
Gwen: (referring to the Trans-Dimensional Monster) Look! That thing has been in here too.
Ben: Only one trail. It either came in here and vanished...
Gwen: ...Or it was born here!

Quotes Right


Kevin: Hey it's that dork from the photo; the Paradox guy.
Gwen: You haven't changed at all - in fifty years!
Paradox: Oh, considerably more than that.

Quotes Right


Gwen: Are you okay?
Old Kevin: My back is killing me, my legs ache, and what's up with these shoes? Is it too much to ask for a little support?
Gwen: He's like a real irritable, short-tempered, crotchety old man.
Old Kevin: Why are you whispering?!
Ben: In other words, aside from the male-pattern baldness, he's pretty much the same as always.

Quotes Right


Old Kevin: You should have gone out with me when I was young and handsome.
Gwen: You were too immature.
Old Kevin: What about now?
Gwen: Too old.

Quotes Right


Old Kevin: You are never driving my car again! (Kevin's car falls apart)
Ben: True.

Quotes Right


Paradox: There is something different about you. Is it your hair?
Old Kevin: Yeah, I'm partin' it down the middle now and I also got real old!
Paradox: Don't talk to me about "old." I walk in eternity.
Old Kevin: Well, you better start running in eternity, smart guy!

Quotes Right


Gwen: Kevin! I can't believe it (hugs Kevin), you're as good as new!
Kevin: Well, my back still hurts a little, if I could just lean on you. (Gwen smiles and pushes him away)

Quotes Right


Ben: (referring to the Trans-Dimensional Monster) You just keep that thing occupied!
Paradox: K-Keep it occupied? I'm a time-traveling hero; I don't keep things occupied!

Quotes Right

Naming and Translations

Language Name Origin
French Voyage au bout du temps Travel to the end of time
Hungarian Paradoxon Paradox
Portuguese (Br) Paradoxo Paradox
Spanish (HA) Paradoja Paradox
Spanish (Spain) La Paradoja De Paradox The Paradox Of Paradox


  • Professor Paradox's line "I walk in eternity" is a direct reference to the Fourth Doctor from Doctor Who, who is often quoted for saying the same thing.
    • Additionally, Paradox offering Swampfire a gumball is also a reference to the Fourth Doctor. Although most Doctors thereafter have done similar things, the Fourth Doctor often offered people jelly babies from a small paper bag.


Voice Actor Role(s)
Yuri Lowenthal Ben Tennyson
Ashley Johnson Gwen Tennyson
Greg Cipes Kevin Levin
Dee Bradley Baker Chromastone
Richard McGonagle General Groff
David McCallum Professor Paradox


  • Kevin's car exploding in case it came with contact with anything from the year 1976 was merely a joke from Paradox.[DM 1]
  • Paradox hinted that he had worked with the future Ben before, and he stated that Ben had decided to transform into Swampfire then too.
  • Paradox mentioned that he and Ben once teamed up to save the entire universe.
  • When Ben, Gwen, and Kevin, and Paradox are in the classroom, there is a music playing in the background that can be heard in a few levels of Ben 10: Alien Force.
  • As of this episode, Jetray's voice is deeper.


Crew Statements

Dwayne McDuffie

Ben 10: Alien Force Episodes
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