Word started going around about Jimmy’s new hot rod a while ago. Jimmy certainly doesn’t know me, he’s just a guy I know of, but everyone said you had to go check out his new ride. He’s been planning this custom-job for like 15 years and that it was going to cost — would you believe this? — half a billion dollars.

After all those years of planning and all that money, it feels a little bad bagging on “Avatar,” but boy, what a lot of hype for the crossover fan-fiction of Jar Jar Binks meets Jarhead in “Fern Gully.”

Main dude Jake Scully, a Sleepy Time Tea-weak Marine whose swear word of choice is “crap” is offered his dead twin brother’s science job on Pandora, where science-types and the military are separately going gaga over root systems and Overwroughtium, a fantastical rock that can be refined into Humvee-fuel, Budweiser or Viagra. That’s more of a range than Jake Scully, who’s pitched the job as he’s watching his brother go into a cardboard coffin and into a broiler. Sculls looks like he wants to take a nap.

Head scientist Sigorney Weaver, who was written as a ball-buster for her first scene, after which, she fades into the background, occasionally emerging to smoke a cigarette, makes a fuss about Scully,

a paraplegic, dangerously not having any training to take on his brother’s avatar, an artificial intelligence body he can project his mind into. Nothing comes of her warning and he bounds off gleefully in his avatar, 20 feet tall, like Tony the Tiger with a dusting of blue glitter. Once in the wilds of Pandora, he’s saved from spiny panthers and hammerhead rhinos by a peppery warrior princess who teaches him

the natives’ ways because the glowing seed tufts of her tribe’s sacred tree landed on him, which means he’s a good guy.

But while Jake has easily agreed to secretly find out how the military can get that ore, he — surprise! — decides he likes these arrow-shooting, war-whooping, horse-riding pagans and their phosphorescent moths and rope-light-branched weeping willows. He positively goes tree-hugging Rainbow Family for them: In a scene where he talks about learning the Navi language, he rolls his eyes, swats his hands and giggles like a school girl when his colleague explains that the native word for “see” doesn’t just mean seeing with one’s eyes, but also understanding someone’s soul. This is a 10-second sequence, but don’t worry. Cameron will belabor it in maudlin “I’ll never let go, Jack, I promise” style later — twice, just in case you were getting popcorn the first time.

After all, Scully’s avatar has legs, and his human mission is predicated on a troglodyte colonel promises him a leg-restoring surgery. Sadly, that’s the force driving Our Hero: the failure of the VA of the future to provide available surgery to a combat-disabled marine. Much as James Cameron loves the reductionist fantasy of romantic, fiery savage with creation stories about “the time of the first songs,” he loves that of evil American military might even more, siccing their gas, bulldozers and fire in a village-destroying CG-gasm, punctuated by the colonel: “and that’s how you scatter the roaches.”

Sure, Jimmy’s latest project is polished, although I have a feeling it will age on DVD like 1983’s “Krull.” The baffling part is, you pop the hood and he’s dropped a four-cylinder engine in there. The inside is all poorly fitted molded plastic and factory stereo. All the halogen headlights and purple neon ground effects can’t change the fact that It rides like a Dodge Caravan. There were some imaginative

flourishes, but at its heart, it’s really nothing you haven’t seen before.

Ashley O’Dell reviews movies that aren’t in the theater anymore. Unless you live in Los Angeles.