It sounded like a stunt. Last year, the English National Opera, cash-strapped and hungry for a big draw, produced a semi-staged revival of Andrew Lloyd Webber’s 1993 musical “Sunset Boulevard” starring Glenn Close — more than two decades after she won a Tony Award in the show’s original Broadway run.

Never mind that the 69-year-old actress was nearly 20 years older than her character, Norma Desmond, the deluded Hollywood star fading into obscurity at 50. The ENO revival became one of London’s biggest stage hits, earning raves for a stripped-down production that returned the focus to Lloyd Webber’s score — and to Close’s performance, which critics lauded as a newly textured and poignant take on the role.

Now Close will reprise Norma at Broadway’s Palace Theater. The New York transfer begins performances Feb. 2 in a production backed by a 40-piece orchestra — the biggest by far on Broadway.

“It’s more focused as a performance, much deeper,” says Lloyd Webber, sitting in the mezzanine of the Palace one morning before tech rehearsals. “For me, with a full orchestra playing the score, I’ve been able get many more colors into the material. I think that’s probably what she feels, too.”

She does. “Norma is much more human now,” Close explains, sitting in her dressing room in the basement of the Palace with her dog, Pip, curled up nearby. “My original Norma was a woman who’s desperately trying to maintain what she was back at the height of her fame and beauty 20 years before. But this time I went back to the movie, and then you add 22 years of life since the last time I played her, and the journey became what she reverts to as she loses touch with reality.”

Jeff riedel for Variety

On Broadway, the production retains its spare aesthetic, with a set dominated by staircases and chandeliers. The costuming has been beefed up, incorporating some of the heavy beaded dresses and robes Close wore in the original production. Even so, with that whopping orchestra, the limited 16-week run remains a pricey proposition.

“The funny thing is, economically, the project doesn’t make a lot of sense,” admits Paul Blake, the American producer (“Beautiful”) tapped by the ENO to shepherd the musical to New York. “But of all the investors we went to, no one turned us down. They all said, ‘Glenn Close! This is going to be an event.’”

Unlike the character first played by Gloria Swanson in Billy Wilder’s 1950 film, Close isn’t receding into oblivion in the recesses of a dilapidated Hollywood mansion. Since she first played Norma, she has taken on the role of Cruella de Vil in the live-action version of “101 Dalmatians” and its sequel; won three Emmy Awards, including two during an acclaimed five-season run in the FX series “Damages”; wrote and starred in her 2011 passion project, “Albert Nobbs”; and returned to Broadway opposite John Lithgow in the 2014 revival of “A Delicate Balance.”

Coming up, she’s reentering the Marvel universe to reprise her role as chief space cop Nova Prime in “Guardians of the Galaxy Vol. 2.”

“I don’t know anything about ‘Guardians of the Galaxy,’ and that’s the absolute truth,” she admits when asked for teasers. “They brought me to the set for one day.”

Before that tentpole’s release, she’ll play a doctor doing all she can to save the human race from a zombie apocalypse in “The Girl With All the Gifts,” opening in limited release at the end of February. “People usually want me to play characters that can easily be the bad one, the villain of the piece, but that bores me,” she says. “There’s enough in this character that she isn’t that.”

“There’s something incredibly compelling about a character who we know is deluded but who clings to this crazy belief that something will happen.”

Close notes that Norma stands out as a meaty gig, even for an actress as busy as she is. “I think she’s one of the greatest characters ever written, certainly for a woman my age. Or even younger!” she adds with a laugh. “There’s something incredibly compelling about a character who we know is deluded but who clings to this crazy belief, with no self-pity — just this great, all-consuming, joyous belief that something will happen. Just to watch the reality overtake her. … She’s a real tragic figure.”

The revivals in London and New York are a chance to return to a character that, she says, haunted her in the weeks after she finished her run in the initial Broadway staging, when she went back to being a mom.

“You do this turn in the theater, and then you go home and you deal with life — taking your daughter to school, all the things that a 6-year-old is into — and it’s like the character is still in your bones and in your sinews. It wasn’t a grieving period exactly, but Norma was definitely still around, saying, ‘What are we doing here making sandwiches?’”

The fact that Close is now more than two decades older brings its own set of challenges. “I’m still very strong, but the role is very, very demanding. And it’s much more emotional now, which takes more muscle.”

Norma becomes increasingly unhinged throughout the course of “Sunset Boulevard,” and in the years since her first go-round with the part, Close has become a vocal advocate for the rights of those suffering from mental illness. In 2010 she co-founded the nonprofit Bring Change 2 Mind, to focus on mental health issues.

“I’m aware of it now in a way I wasn’t before,” she says. “Of how mental illness might manifest itself in a way that’s not explained, but that’s certainly a part of her behavior. Absolutely.”

The actress, who’s based in New York, finds theater work far more consuming than her film jobs. “Theater totally takes over,” she says, describing the hour prior to each performance she spends doing vocal exercises with the orchestra’s conductor. There are also the ongoing efforts to stay healthy: sleeping a lot, exercising, and stretching regularly. “We all become super vigilant,” she says of the cast. “And hypochondriacs! Purell all over the place. You don’t want to miss a show.”

“Sunset Boulevard” is set to finish up its Broadway run May 28. But even after that, Close may get one more chance to play Norma: There have been talks with Paramount about a film adaptation of the musical.

“I would love it to happen, and I can’t think of anybody better to play Norma,” Lloyd Webber says.

The actress is certainly on board. “I hope!” she echoes. “We’re all ready.”