After a nice “Pinocchio”-like start, this new film adaptation of “Astro Boy” goes depressingly to the dogs.

A subpar companion piece to “WallE,” this American-Hong Kong co-production resurrects an iconic Japanese manga set in a future in which “floating paradise” Metro City sails above burned-out, rubbish-strewn, “Mad Max”-like Earth, where citizens scratch out meager lives while Metro City-zens party.

Run by warmongering Gen. Stone (Donald Sutherland), Metro City offers its citizens robots for all purposes, virtual slaves that keep the place clean and running, cater to the lucky human owners’ every need and even fight wars for them.

Like I said, promising start. In scenes channeling “RoboCop,” the General takes a limitless power source discovered by genius scientist Dr. Tenma (Nicolas Cage) and uses it to create a super-robot soldier. Tenma, part Dr. Frankenstein, part Geppetto, uses another, even better power source to create a DNA-based robo-substitute for his beloved, neglected son Toby (Freddie Highmore) after a horrible accident vaporizes the boy.

The resulting cute, super-powerful, robotic entity is Toby-like, but also not Toby, and his grieving creator and father rejects him (paging “Artificial Intelligence: A.I.”).

After plummeting Icarus-like to the surface, the robot encounters a trio of revolutionary ’bots, including a talking fridge, and befriends a ragtag band of Earth children headed by the generically spunky girl Cora (Kristen Bell). The plot further involves robot gladiatorial combat, a tiresome, manipulative blowhard named Ham Egg (Nathan Lane), “butt guns” and a barking, canine-like character dubbed Trashcan.

The setup and the effects and fight scenes surrounding it are very promising, indeed. But the flagrant derivativeness (Isaac Asimov’s estate should sue), banal dialogue and pathetic attempts at humor are sore reminders that this is no Pixar film.

Created by manga visionary Osamu Tezuka, Astro Boy retains his signature Bela Lugosi-esque, oddly double-peaked hairstyle, puppy-dog eyes, overall cylindrical design, massive weaponry and chirpy personality. He’s Iron Man’s Mini-Me and with any luck he’ll survive this hamhanded reboot. The film’s look combines traditional manga and more modern styles.

Director David Bowers, who co-wrote this heavily indebted script with Timothy Hyde Harris (“Kindergarten Cop,”), did a much better job with his first effort “Flushed Away” (2006).

Rated PG. At AMC Boston Common, Regal Fenway Stadium and suburban theaters.

(“Astro Boy” contains gun-related violence, explosive action and lame jokes “voiced” by Nathan Lane.)