To the many fearsome pop-cult monsters that have been made in Japan--Godzilla, Mothra, Kitaro--we can now add Pikachu. A bright-eyed, baby-talking yellow creature with a lightning-bolt tail, the star of "Pokemon: The First Movie" is perhaps the most formidable cartoon rodent since Jerry. Yet Pikachu's electrical superpower is not enough to energize his movie, a dull, crudely animated Pokemon byproduct that didn't noticeably juice the predominantly under-12 crowd at a recent preview.

Any adult who is likely to see "Pokemon" is probably already acquainted with someone who knows all about Pikachu. In fact, that person probably lives right down the hall. By all means, take this expert with you to the theater; his or her guidance will be essential to understanding Pokemon--which your resident expert can tell you is short for "pocket monsters"--and their cartoon-human trainers.

Americanized by director Michael Haigney from the original Japanese feature directed by Kunihiko Yuyama, "Pokemon: The First Movie" features Ash Ketchum and his fellow Pokemon trainers Misty and Brock, the heroes of the series on the WB Kids! network.

Ash and other trainers teach their Pokemon to fight, a drill that started in a video game and continues in the popular trading-card game, on the television show and now on the silver screen. Pokemon are brawlers, but they're also shamelessly cute in the customary Japanimation mode. Think of them as the samurai class of the Beanie Babies age.

Perhaps in response to the controversy over video game violence, the 151 varieties of Pokemon--collect 'em all!--were designed to be invulnerable. As long as their trainers are vigilant, the creatures can be hurt but not killed. Considering that they're endowed with such superpowers as the ability to spray water (Squirtle, a turtle) or shoot leaves and vines (the part-planter, part-reptile Bulbasaur), even serious injury seems unlikely. Cuddly, playful and babyish as he appears, the electrically charged Pikachu is one of the more intimidating Pokemon.

The movie's main event is a battle between Ash and Mewtwo, who is identified as the most powerful of the Pokemon. (My 7-year-old guide insisted he's not.) Cloned from the catlike Mew, Mewtwo is angry and misguided but not bad to the Poke-bone. He's indignant that scientists trifled with nature, a recurring theme in Japanese animation, so he invites Ash and other trainers to his island for a showdown. In the annals of cinematic warfare, this listless clash is no competition for "The Seven Samurai"--or even for the PG-13 "Princess Mononoke," which is to "Pokemon" what Bob Dylan is to "Pokemon" soundtrack stars Baby Spice, M2M and Christina Aguilera.

The movie's clash of the roly-poly titans ends with a character revived by the tears of the empathetic Pokemon, and a moral that should put most Pokemon skeptics at ease: "This just proves that fighting is wrong." Considering that Pokemon exist to fight, that conclusion seems to limit the options for the sequel that the movie's title virtually promises. But perhaps "Pokemon: The Second Movie" will be a Bergmanesque psychological drama.

That's a preposterous notion, but it's less absurd than "Pikachu's Vacation," the surrealistic short that precedes each "Pokemon" screening. A series of seemingly unrelated events that transpire at a resort for Pokemon, the cartoon is the weirdest thing to hit local screens since "julien donkey-boy." It's an animated outbreak of dadaism, a journey to the outer limits of narrative, where Zippy the Pinhead might feel at home but more literal-minded viewers will be confounded. (My 11-year-old guide admitted bewilderment.)

If the purpose of "Pikachu's Vacation" is to make the limply plotted feature seem coherent by comparison, it succeeds. But in the process, it also makes "Pokemon" look far stodgier than any movie starring a bright yellow mouse with a lightning-bolt tail should be.

Pokemon: The First Movie (89 minutes, at area theaters) is rated G.

CAPTION: The "pocket monster" craze moves from video games and trading cards to "Pokemon: The First Movie."

CAPTION: Pikachu and Ash in "Pokemon: The First Movie."