It's rarely a good sign when a high-concept popcorn pic top-lining a proven B.O. performer gets dumped into release during the dog days of August. And, "Zoom" lives down to the worst expectations. This tepid comicbookish comedy should zip through its theatrical run faster than a speeding bullet. It likely won't perform much more superheroically in ancillary venues.

It’s rarely a good sign when a high-concept popcorn pic top-lining a proven B.O. performer gets dumped into release during the dog days of August. And, “Zoom” lives down to the worst expectations. Released Aug. 11 with a minimum of hoopla and no press preview screenings, this tepid comicbookish comedy should zip through its theatrical run faster than a speeding bullet. It likely won’t perform much more superheroically in ancillary venues.

After his sharply satirical performance in “Galaxy Quest,” Tim Allen might seem perfect for the lead in another semi-spoofy sci-fi misadventure. But the actor merely goes through the motions here as Jack Shepard, a has-been superhero who hung up his cape after his similarly powerful brother went over to the dark side. The under-achieving “Zoom” resembles nothing so much as a subpar episode of a failed Disney Channel teleseries.

In his heyday, Jack was Captain Zoom, a superspeedy sprinter admiringly described as “faster than Quicksilver, the Flash and Superman combined.” He was first among equals in Team Zenith, a dream team of superheroes assembled for a top-secret government project led by hard-ass Gen. Larraby (Rip Torn) and klutzy Dr. Grant (Chevy Chase).

But when Team Zenith was “enhanced” with massive doses of gamma radiation, the sonic-blasting Concussion (Kevin Zegers) devolved into villainy. After a big brawl, Concussion was zapped into another dimension — but not before decimating Team Zenith. Jack, the sole survivor, allegedly lost his powers and opted for early retirement.

Helmer Peter Hewitt (“Bill and Ted’s Bogus Journey”) provides this exposition in a zippy prologue aptly illustrated with panels from “Captain Zoom” comicbooks. After that, however, it’s all downhill as pic unfolds as a charmless and mirthless time-killer. In the process, it inadvertently illustrates how easily last year’s vastly superior “Sky High” could have gone dreadfully wrong.

Thirty years later, Jack unretires to train a group of prospective superheroes, ranging in age from 6-17, as a defensive measure against the impending return of Concussion.

Among the callow recruits: Tucker (Spencer Breslin), a chubby middle-schooler who can massively expand various body parts; Summer (Kate Mara), a telekinetic empath who’d rather be a high school cheerleader; Dylan (Michael Cassidy), a dreamy hunk who can make himself invisible and “see” faraway activities; and Cindy (Ryan Newman), a fantastically strong moppet with a unpleasant streak of spoiled-brattiness.

This new Team Phoenix needs all the help it can get, but Jack initially is reluctant to serve as their mentor, despite the fervent encouragement of nerdy Dr. Marsha Holloway (Courteney Cox). Only after a very long stretch of none-too-funny hijinks does the ex-superhero have a change of heart.

The vets in the cast are ill-served by the thin script — adapted by Adam Rifkin and David Berenbaum from a graphic novel by Jason Lethcoe — but that doesn’t completely excuse their rote performances. On the other hand, it’s hard not to feel sorry for Cox, who is called upon to slip or trip whenever the pic needs an easy laugh. Cox falls down a lot in “Zoom.”

As for the unremarkable newcomers in the cast: If they’re going to be breakout performers, they’ll have to find something better to break out of.

And the special effects aren’t very good, either.

Zoom

Production

A Sony Pictures Entertainment release of a Columbia Pictures and Revolution Studios presentation of a Team Todd/Boxing Cat Film production. Produced by Suzanne Todd, Jennifer Todd, Todd Garner. Executive producers, Nicholas Osborne, Trevor Engelson, Neil Machlis. Co-producer, Julie Ragland. Directed by Peter Hewitt. Screenplay, Adam Rifkin, David Berenbaum, from the screen story by Rifkin, based on the novel "Zoom's Academy for the Super Gifted" by Jason Lethcoe.

Crew

Camera (Deluxe color), David Tattersall; editor, Lawrence Jordan; music, Christophe Beck; music supervisor, John Houlihan; production designer, Barry Chusid; art director, Joshu de Cartier; set decorator, Clive Thomasson; costume designer, Ha Nguyen; sound (Dolby Digital/SDDS/DTS), Robert Scherer; visual effects supervisor, Marko Forker; assistant directors, Jeff Authors, Matt Rebenkoff; casting, John Papsidera. Reviewed at AMC Meyer Park 16, Houston, Aug. 11, 2006. MPAA Rating: PG. Running time: 88 MIN.

With

Jack Shepard/ Captain Zoom - Tim Allen Marsha Holloway - Courteney Cox Dr. Grant - Chevy Chase Tucker Williams/ Mega-Boy - Spencer Breslin Connor Shepard/Concussion - Kevin Zegers Summer Jones/Wonder - Kate Mara Dylan West/Houdini - Michael Cassidy Cindy Collins/Princess - Ryan Newman Larraby - Rip Torn
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