The most important questions can seem the most trivial: At the Wednesday opening of the Walnut Street Theatre's new production of

Les Miserables

, could the ultra-durable musical survive without its famous revolving set design?

Well, yes, but not without seeming less indestructible than in the past.

Having played just about everywhere,

Les Miserables

is in its third decade with a new chapter: Previously, this musicalization of Victor Hugo's saga of class struggle - in which ex-convict Jean Valjean achieves heights of redemption and nobility that few of us will ever know - was seen only in versions of the original production, in which director Trevor Nunn and designer John Napier conspired to capture the story's sprawling sweep with a series of short, intense scenes greatly facilitated by a stage turntable that allowed scene changes with cinematic detail and speed.

Though the show's score, by Alain Boublil and Claude-Michel Schönberg, is dramatically serviceable and memorably tuneful, and though Hugo's characters are timeless archetypes, the production is what facilitates cumulative literary impact while maintaining the rhythm of commercial theater. Extra seconds needed to take us into the Paris uprising of the 1830s could fatally elongate the near-three-hour show.

So the Walnut crew confronted a challenge that was greater, actually, than it looked: To triumph, in this case, is to give a business-as-usual impression. And that they do.

The new production looks and feels very much like the old, with eroding building exteriors that lend themselves to the show's numerous downtrodden locales, with more specific scenery arriving from the stage wings via double-decker wagons. The turntable versions of

Les Miz

had the action gravitating toward the center of the stage. At the Walnut, though there is less visual variety than in the original, director Mark Clements utilizes Todd Edward Ivins' design to send the action spilling out into the aisles in more functional moments, but also has it inhabiting the sides of the stage for worthy purposes.

Characters who got lost in the original no longer do. The best example is Gavroche, the kid who used to come out of nowhere for his few heroic scenes on the Act 2 barricades but who in fact had a nice character exposition much earlier, one that's now set off on an extreme side so you can't miss it. Such details make the show the epic that it is - even with a puny-sounding orchestra.

The opening-night audience seemed primed to love it all, with cheering as automatic as a TV laugh track - as you'd expect for a show whose story has a significant character dying in every third scene and whose score has skillfully positioned "money notes" every three minutes. Things grew surreal, though, when even the famous barricade of Act 2 was wildly applauded as it came forth from the rear of the stage. Anyplace else, you'd have fretted over why a hunk of wreckage was coming at you.

Less Pavlovian

Les Miz

goers must cope with memories of the last touring production, whose cast was in peak condition. This one had some undercooked characterizations that made the performance feel like a rerun. That's a significant problem:

Les Miz

is thought to be actor-proof, but for the show's repeat customers it's anything but, especially when main characters have found only the outlines of their roles. That should change as the run goes on, but you're not likely to get some of the quirky cabaret-style performances that might distinguish a European production.

On Wednesday night, Julie Craig and Josh Young were fairly standard as the young lovers Cosette and Marius. As Javert, Paul Schoeffler sometimes seemed lost: His portrait of righteous obsession curiously lacked zeal. Having played Marius 20 years ago, Hugh Panaro is now Jean Valjean, and though he has convincingly aged in the later scenes, his brilliant money notes mask what's missing elsewhere. Though suitably predatory as a tavern owner, Scott Greer was too winning to be menacing.

The main exception to this rerun status is Christina DeCicco, who played the self-sacrificing Eponine with such charm and refreshing lack of self-pity you couldn't believe anyone would resist her. Then she sang and showed you her soul.

Les Miserables

Through Aug. 3 at the Walnut Street Theatre, 825 Walnut St. Information: 215-574-3550 or walnutstreettheatre.org.

Contact music critic David Patrick Stearns at dstearns@phillynews.com.