When Ben Tennyson first put on the fancy genetics-altering wristwatch called the Omnitrix, it was just an idea in the heads of the writers' collective called Man of Action. Sure, they hoped they had a good idea for a cartoon series. Probably toy spin-offs danced in their heads, but live action had to have been the furthest thing from their minds. After all, this was Cartoon Network.

For the second time, however, Cartoon Network has adapted Ben 10 to a live film, tonight launching Ben 10: Alien Swarm. Like its predecessor, Ben 10: Race Against Time, it may shrink the canvas of Ben's adventures a little bit, but it's still surprisingly faithful to its cartoon roots and thankfully, entertaining.

Following the revision set in the earlier movie, Ben (Ryan Kelley) and his cousin Gwen (Galadriel Stineman) work directly for their grandfather Max (Barry Corbin - replacing Lee Majors) as members of "The Plumbers," a secret organization dedicated to fighting off alien invasions. Apparently, this happens more often than you'd think, and one of the slyest jokes in the script by John Turman and show writer James Krieg is how casually everybody takes this. So secret and yet so not.

With their friend Kevin (Nathan Keyes), who has powers roughly akin to Marvel's Absorbing Man, the Tennysons investigate a black-market in alien technology, micro-chips that come alive and swarm at the command of a mysterious figure in a trenchcoat.

They discover it's a set-up, of sorts, as a disgraced Plumber's daughter Elena (Alyssa Diaz) needs their help in finding her father. She believes he's been kidnapped because of what he knows about alien tech; the truth may be far darker, and Grandpa Max forbids everyone to help.

But hey, they're teen-agers, and following orders is one of the things they do worst. Good thing, too, because there's a stealth invasion happening, and Max's fool pride blinds him to it.

The script assumes familiarity with the characters' backgrounds that a newcomer wouldn't have, but it also delineates characterization quickly and easily. Our hero Ben is earnest, a lot more popular in high school than he was in middle school, and always trying to do the right thing. Flirting with bad boy status, Kevin seems to be begrudgingly on the side of good, if only because he has a thing for Gwen. As for her, she has vague energy related powers, and seems to be waiting for both of her boys to grow up.

But they do so well as teen heroes. That may be because director Alex Winter spent some time as a likeable teen hero himself, the unlikely William S. Preston, Esquire of Bill and Ted. He knows how to make the somewhat goofy seem sincere without crossing over into ridiculousness, and he draws decent performances out of all the teen actors.

Whether it's him or a canny casting director, there's also a sharp eye here for quirky actors that can make the smallest part memorable. In particular, nice work for casting Herb Siguenza of the Latino theater collective Culture Clash as Elena's father, Validus. (A reference to the Legion of Super-Heroes? The trio does function in personality like Cosmic Boy, Lightning Lad and Saturn Girl.)

A concept like Ben 10, though, can't fly just on acting - there has to be action. Winter moves that part along well, too, covering for the smaller scope of television by keeping everything moving at a brisk pace and making the most of each location. Even though the story only has a few sets to it, it feels just right.

Most impressive of all, Winter has a budget to do a pretty good job with the super-powers. The CG alter egos of Ben 10 all look good, though I'd have liked to have seen more of them. Then again, even the animated series keeps each episode down to only two or three alien identities. The production also proves that you can have absorption powers look surprisingly effective without spending a lot of money; Winter does more with Kevin's powers in the first fifteen minutes than Ang Lee did in all of Hulk.

I'll admit, I'm armed with a rabid five-year-old who loves, loves, LOVES Ben 10, so I would have had to have watched this no matter what. But this is solid work, coming from a mythos that really is reaching kids and giving them heroes of their own instead of ones we're passing down and obsessively quizzing them on. (Seriously, can't every kindergartener name the founding roster of the Justice Society?) Check out Alien Swarm; it might open you up to a new franchise, and it's not a bad way for a fanboy family to start Thanksgiving.

Now if we could just get a decent comic book going out of it…

Where: Cartoon Network
When: Wednesday, November 25, 7 p.m.