In the TV commercial, a determined, and somewhat anxious little boy stomps through Disney World. There will be no rides or other amusements for him, he informs his parents, until he gets a chance to meet and greet that great American icon, Mickey Mouse. Then, magically, the bright-eyed rodent appears before the lad, and the little tyke is struck dumb with awe and joy.

Ah, to be four again! To see some dude (or dudedess) in red pants, big shoes, and an oversized plastic puppet head, and somehow believe that you're actually meeting a favorite cartoon friend---wouldn't that be swell?

You bet it would. And that is why even those of us who are old enough to know better have always been enchanted by movies that mix animation and live action, cartoons and a "real" world.

In the 1920s the Fleischer brothers produced their KoKo the Clown cartoons, in which their hero emerged "Out of the Inkwell" to move through photographed environment. Conversely, in Walt Disney's earliest "comics," the Alice comedy shorts, a real little girl interacted with animated characters and illustrated backgrounds

So, from the early days of films, these two realms have converged on screen. Because of the labor-intensive and technically challenging nature of animation/live-action hybrids, the classic examples were either short films, or cartoon-enhanced interludes in acted films.

Most of us can remember at least a few such screen gems: Gene Kelly and Jerry (the mouse) dancing together in Anchors Aweigh (1945); Dick Van Dyke making merry with a chorus line of penguins in Mary Poppins (1964); or, Lily Tomlin having a Snow White fantasy, complete with animated fauna, in the gender farce, 9 to 5 (1980).

Then there was Who Framed Roger Rabbit (1988), a movie as fresh and visually stunning today as it was when it was first released. (If you have never seen this movie, put this review down, and immediately go out and rent or buy it on tape or DVD! That's an order, buster!)

A pitch-perfect blend of classic cartoon zaniness and Chandleresque hardboiled mystery, Roger Rabbit also brought animation and live action together in a way that was seamless and utterly believable-and sustained the illusion for almost two full hours.

It helped to have a magician like Robert Zameckis at the helm. And it was essential to have top-of-the-line (if not superstar) actors in the live-action roles. No matter how carefully animation is integrated into a live scene, if the human player can't make you believe that he's handcuffed to a frenetic rabbit, or that he is speeding through town in a cartoon cab, then the realism of the fantasy cannot work.

While preparing this piece, I recently re-watched Who Framed Roger Rabbit, and was mesmerized, again, by Bob Hoskins's performance as private eye, and 'toon-hater, Eddie Valiant. The man is bleepin' brilliant. And so were the animators and voice actors who created his co-stars.

When I first saw Roger Rabbit, I remember thinking that here was the breakthrough-the watershed-the movie that open up a brave new world of moviemaking.

Little did I know that with all the technical progress of the last decade, the artistry of Roger Rabbit would still set it apart as the best example of Animation/Live Action moviemaking.

What came after, hasn't come close.

Cool World, Ralph Bakshi's 1992 two-worlds-collide drama, was a fiasco from beginning to end. The acting was pathetic. (Brad Pitt is a lovely young man, but he will never be the actor Bob Hoskins is.) And the integration of animation to live action was surprisingly badly meshed. To add to the disappointment, the story was incoherent, the screen action chaotic, and the cartoon characters were repellent, especially the two "doodle" babes who try to tempt the " 'noid" heroes into doing the nasty with them.

Space Jam (1996) was better, but not by a lot. Michael Jordan and the Warner Brothers stable of cartoon characters made for a high-concept pitch, but a mediocre movie.

But, even so, it was a more satisfying movie than last summer's Adventures of Rocky and Bullwinkle, directed by Des McAnuff. What the heck was screenwriter Kenneth Lonergan thinking when he wrote this drivel? (And how is it possible for the same guy to have written and directed the brilliant sibling comedy-drama, You Can Count on Me?) Lonergan's screenplay makes many small missteps and one absolutely fatal error: it transforms America's best loved cartoon baddies into humans. I like Renee Russo and Jason Alexander. But, come on! I want Boris to be a cartoon Boris. And I absolutely require that the fabulous Natasha Fatale be a cartoon Natasha.

If you're going to contrast the 'toon world with the human, keep it straight who's a human and who's a cartoon. Sadly, even though Rocky and Bullwinkle remain "animated," they are remarkably lifeless creations. The computer-generated techniques used to "draw" them produced muddy colors and cold images. And, odder yet, little Rocky seems to have a peevish expression on his face much of the time. The flat, almost crude animation of the original series had much more natural warmth and humor.

You get the sense that the people who made the movie had a real affection for the old cartoons. They just didn't know how to translate that affection into a watchable feature film. Indeed, I suspect it was an impossible task, with just Rocky and Bullwinkle to work with. Moose and Squirrel might have been the titular stars of the original series, but, let's face it, the best segments of the series were the "Fractured Fairy Tales," the "Aesop & Son" fables, and, above all, the "Improbable History" adventures of Mr. Peabody and his boy, Sherman. Without these cartoon stars to spice up the cast, the project was doomed from the get-go.

And so, I fear, was Monkeybone, a film that integrates stop-motion animation with live action. Directed by Henry Selick (who did such fine work with Tim Burton's Nightmare Before Christmas, and James and the Giant Peach.) Monkeybone was written by Sam Hamm from a graphic novel by Kaja Blackley, illustrated by Vanessa Chong.

The film opens with a shy cartoonist named Stu Miley (Brendan Fraser) hitting it big. His cartoon series about Monkeybone, an impish monkey (and none too subtle Jungian manifestation of his unbridled id), has been picked up by a network, and is about to strike merchandizing gold.

Stu seems ill-suited for fame and fortune, however. All he really wants to do is go home and propose to his doctor girlfriend, Julie (Bridget Fonda). But before he can, an auto accident sends him into a coma, whereupon he descends into a netherworld called Downtown.

Here is where the movie Monkeybone should be its most entertaining. It is not. Downtown is a dark chaotic carnival camp full of characters in bad costumes and big puppet heads. The film implies that this is a limbo territory for all souls between life and death. But it looks like a freak show and nothing more.

Except for Stu, no one else seems to be waiting to wake up and get on with life. Indeed, none of the denizens of Downtown look like they've ever even been on Earth. That is, except for a few incarcerated folks like Attila the Hun, Lizzie Borden, and---even more absurdly---Stephen King. (Hey, don't ask me! I just write the reviews.)

There's one other creature Stu meets up with in Downtown, of course. And that is his own errant cartoon creation, Monkeybone. As you might imagine, the movie ultimately succeeds or fails on the ability of this little cartoon critter (voiced by John Turturro) to amuse and delight an audience. Think Curious George on mescaline and Viagra, and consider whether you'd want to spend over 90 minutes in his company. Thought not.

Mr. Selick, who knows animation very well, inexplicably fails to give Monkeybone much facial expression, and Turturro's voice is all whine and chatter. In the end, the character of Monkeybone has little personality, just a penchant for annoying the hell out of people forced to watch his frenetic actions.

The rest of the plot relates to Stu's attempts to steal an exit pass from Death (an unhappy looking Whoopi Goldberg), and Julie's attempts to bring Stu out of his coma before her lover's inexplicably callous sister (Megan Mullaly, doing Karen schtick) pulls the plug on his life support.

Monkeybone doesn't make a lot of sense, and, worse, makes little creative use of the contrast between animation and action.

In The Adventures of Rocky and Bullwinkle, the best part of the movie is the establishing cartoon bits at the beginning, and a mid-movie animated scene in which Bullwinkle has to travel up the Northeast corridor in an email, surfing the web as he goes.

In their natural pen and paint environment, Rocky and Bullwinkle shine. But they seem as dull as dishwater, and completely out of place, in a live action world. Hence, their "Adventures" never connect with viewers.

On the other hand, in Monkeybone, the best scenes involve actors in live-action locales. In one hilarious segment, Fraser's Stu, temporarily possessed by Monkeybone, attempts to make jungle love to a stunned Julie. In another scene, Stu, in desperate need of another body, re-animates the earthly remains of a dead gymnast and organ donor, played by SNL's Chris Kattan. Inside, he's a man in love, outside he's a decomposing corpse with a broken neck and organs spilling out of his sliced torso.

It's gross, stupid, but undeniably funny stuff. No cartoon characters were involved. Nor were they missed.

Who Framed Roger Rabbit proved that you can make a great feature movie by exploring the intersection of the real and the fantastical, the human and the 'toon. Movies like The Adventures of Rocky and Bullwinkle and Monkeybone prove that just inserting cartoon characters into live action, or actors into make-believe settings, doesn't automatically translate into screen magic.