Who is he? Who is he?

He’s Ramin Karimloo, and as Jean Valjean, he’s the main reason to reacquaint yourself with the “newly reimagined” revival of “Les Miserables,” now open at the Imperial Theatre.

Sentimental? The Imperial is where “Les Miz” ran for the lion’s share of its original run, which ended just over a decade ago. Since then, it’s been hard to miss the epic story based on Victor Hugo’s novel, because it never really went away. “Les Miz” returned to Broadway in a slimmed-down 2006 revival, and hit big screens in 2012.

Why is “Les Miz” back on Broadway so soon? And should it be welcomed, like a street urchin invited to tag along with a gaggle of revolutionaries?

The answer to the latter is yes, absolutely. An answer to the former is more intricate. Producer Cameron Mackintosh launched this “Les Miz” four years ago, in recognition of the musical’s 25th anniversary in London. New orchestrations were added, and designs inspired by Hugo’s sketches were incorporated into the set—entering the Imperial, you’ll note the Parisian cityscape on the curtain bears Hugo’s signature.

At the same time, Susan Boyle’s 2009 star turn on “Britain’s Got Talent” helped introduce the Alain Boubil and Claude-Michel Schonberg musical to a new audience. It’s this fine-tuned effort that inspired parts of Tom Hooper’s 2012 film. You’ll see the similarities in the scenery of Valjean’s Paris home, and as Javert (Will Swenson, of “Hair” and “Priscilla”) takes his death plunge into the swollen Seine.

But first, back to Prisoner 24601, the convict imprisoned for stealing bread to feed his sister’s children, and pursued for decades by the single-minded Inspector Javert. Karimloo is the Tehran-born, tattooed Mackintosh discovery who has played leads in the West End versions of “Phantom” and “Les Miz,” and starred there in “Love Never Dies,” Andrew Lloyd Webber’s “Phantom” sequel. He performed Valjean recently in Toronto, and makes a powerful impression in his Broadway debut.

This “Les Miz” has a sharply delineated prologue. Valjean receives his yellow ticket of leave, and then a backdrop introduces the musical’s title, but not before the brawny Karimloo rips open his shirt and boldly announces his transformation: “Jean Valjean is nothing now! Another story must begin!”

Make no mistake, this “Les Miz” is Karimloo’s story. I was awed by the actor’s soaring voice, particularly during the final notes of “Bring Him Home,” which seem to last blissfully forever. He’s captivating and charismatic.

Otherwise, this revival is a successful love-letter to the original, with some nifty tweaks. The male leads skew younger than they have in past productions (Karimloo is 35). Out is the familiar turntable, which once spun an enormous barricade; in is a video backdrop that transitions from a streetscape to the Paris sewers as Valjean rescues the gravely injured Marius (a fine Andy Mientus, late of “Smash”). The show just looks dynamite.

Judging by audience reaction at a recent press performance, there was great enthusiasm for Will Swenson’s Javert. I think Swenson is wonderful. His vocals are strong and even, and it’s hard to believe this is the same guy we just saw in the sleepy “Little Miss Sunshine.” 

Ultimately, the dynamic between his Javert and Karimloo’s Valjean feels a bit askew. How could anyone, really, possess the gravitas of this Valjean, and thus seem a suitable rival? Still, Swenson’s second act soliloquy, in which he pledges to escape from the world of Jean Valjean, is a high point.

Caissie Levy, who originated lead roles in “Ghost” and “Hair,” has frailty and a velvety-soft voice as the tragic Fantine, who sells her jewelry, her hair and her body to send money home to her young daughter. I was moved by “I Dreamed a Dream” in ways I haven’t been in years.

Nikki M. James, the Tony-winner for “The Book of Mormon,” has spunk as Eponine, whose unrequited love for Marius is so easily relatable. Samantha Hill, reprising a role she recently played in Toronto, makes for a pleasing, if unmemorable, adult Cosette.

Kyle Scatliffe is a commanding Enjolras in his Broadway debut, one you’d certainly follow into battle. Mientus has a nice balance of confidence and innocence in his Broadway debut, particularly during “Empty Chairs at Empty Tables.”

Tony-nominee Keala Settle (“Hands on a Hardbody”) is a scenery-chewing Madame Thenardier, particularly during “Master of the House,” as she rips apart a loaf of bread until it’s just a stub, singing of her husband: “Thinks he’s quite a lover, but there’s not much there.” As her sketchy spouse, Cliff Saunders seems to be emulating a particularly enraged Chucky doll.

It would be an omission to leave out the winning performance by young Gaten Matarazzo (he was also in “Priscilla”) as Gavroche, who here has a lisp that somehow makes him more multi-dimensional. I was never sure if it was part of the character, or how the child actor speaks, but he’s very good.

At the end of the third hour, the story resolves with a beautiful tableau: the departed Fantine, Eponine and Jean Valjean stand behind a kneeling Marius and Cosette. It’s an intense moment. I have a number of people in my life otherwise uninterested in musicals, but utterly taken with “Les Miz.” This production reinforces why: among all the well-played roles, it’s inevitable you’ll find someone who speaks to you.

“Les Miserables,” with an open-ended run at the Imperial Theatre, 249 W. 45th St. Tickets: $57-$139. Call 212-239-6200, or visit Telecharge.com.

Follow Robert Kahn on Twitter@Robert Kahn