By Claudia Puig, USA TODAY

"They'll come back because we'll need them to," says Samuel L. Jackson as Nick Fury about the Avengers, the superheroes he commands.

Of course they'll be back, thanks to Hollywood's obsession with sequels, especially those based on comic book heroes. Their return is guaranteed also because audiences have been eagerly anticipating this first all-hero extravaganza for years. The wait was worth it.

They've all been around the blockbuster block, individually or in smaller combinations. Now this group of a half-dozen heroic comic-book characters fights a dastardly villain on land, air and into outer space. But they also amusingly tussle among themselves. It's that last squabbling that makes for the most fun.

Marvel's The Avengers (*** out of four, PG-13, opened at select theaters at midnight, nationwide Friday) offers maximum bang for moviegoing buck. Audiences are treated to the snarky wit of Iron Man (Robert Downey Jr.), the unmanaged anger of the Incredible Hulk (Mark Ruffalo), the patriotic derring-do of Captain America (Chris Evans), the hammer-wielding Norse justice of Thor (Chris Hemsworth), the sly fearlessness of Black Widow (Scarlett Johansson) and the fiendishness of arrow-wielding Hawkeye (Jeremy Renner).

It's essentially six movies in one, which might account for the nearly 2½ hour length. While it's slow getting started, The Avengers is a splashy superhero mash-up that should please breathless fanboys.

It also has a broader appeal for mass audiences with its fast-paced comic banter and exhilarating action sequences under the capable helm of director/co-writer/unabashed fan Joss Whedon.

Whedon weaves a story that allows each of the heroes to do what they do best. And while they may not have exactly equal time, audiences get enough of each to feel satisfied, but not sated. Clever work, indeed.

Downey's playboy millionaire/scientist Tony Stark (Iron Man) verbally jousts with straight-arrow Steve Rogers (Captain America), whose earnestness is delivered pitch-perfectly by Evans.

Not surprisingly, Downey gets the funniest lines. On another planet, he battles Hemsworth's Thor, who intones his stentorian dialogue with the superhero equivalent of a wink. Ruffalo as Bruce Banner/Hulk pulls off some of the best physical gags, making for a much more fun Hulk after the last few disappointing incarnations.

Clark Gregg, as Nick Fury's second-in-command Phil Coulson, has some well-timed comic zingers in a plot that hinges on a power cube known as a tesseract and the megalomaniacal grab for it by the evil Loki (Tom Hiddleston), last seen as the jealous brother of Thor in last summer's eponymous blockbuster.

Whedon wisely gives the group the appeal of a comic ensemble, so when the 3-D battles with alien armies grow numbingly familiar, the breezy comic dialogue, divvied up among the collective, makes for a happy and welcome distraction.