How do young stars deal with sudden fame?

That was him once — on your soda cup, at your newsstand, stuck on the side of your bus.

At 19, Hayden Christensen was still baby faced when he was handpicked by George Lucas to lead the new “Star Wars” prequels. The Canadian teen had never set foot on a major film set before shooting “Episode II” in 2002. Everyone, including Lucas, told him that playing Anakin Skywalker would change his life.

Still, Christensen found himself unprepared for sudden fame. He felt undeserving, as if he hadn’t earned his acclaim in any meaningful way. So even though he had an acclaimed starring role in the 2003 plagiarism drama “Shattered Glass” and appeared sporadically in other films, after the release of “Episode III” in 2005, the actor bought some farmland and largely retreated from Hollywood.

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“I guess I felt like I had this great thing in ‘Star Wars’ that provided all these opportunities and gave me a career, but it all kind of felt a little too handed to me,” the actor said this fall, promoting his first movie in five years, a faith-based drama called “90 Minutes in Heaven.” “I didn’t want to go through life feeling like I was just riding a wave.”

It’s hard to imagine Daisy Ridley or John Boyega, the 23-year-old stars of “The Force Awakens,” someday revealing similar inner turmoil. Like Christensen, each of the British actors was largely anonymous before being cast by J.J. Abrams last year. Ridley didn’t even have a page of credits on IMDb. But both seem to be embracing their newfound fame.

Since the “Star Wars” promotional machine began churning in April at Disney’s fan event Star Wars Celebration, the two former unknowns have been virtually everywhere. Ridley landed on the covers of Elle and Glamour UK, even though readers had yet to see her on the big screen. She and Boyega appeared in a “Saturday Night Live” skit spoofing the film’s audition process.

And by the time they walked the red carpet at the movie’s premiere in Los Angeles this month, they were already designer darlings: Ridley wore a dress that had been designed for her by Chloé Atelier, while Boyega sported a custom three-piece Versace suit with a single leather glove.

It’s rare, of course, for novice actors to generate this much publicity. Every year at the Sundance Film Festival, for instance, there’s always some pretty young thing whom the media fixate on, but the frenzy quickly dissipates once everyone leaves Park City, Utah. Same goes for awards season. Pundits are quick to name the next Meryl Streep, but after the Oscars are handed out, many — think Catalina Sandino Moreno (“Maria Full of Grace”) or Haley Joel Osment (“The Sixth Sense”) — struggle to maintain momentum.

Landing the lead in a big-budget film franchise certainly gives a young actor a better shot at stardom. For one thing, moviegoers are guaranteed to come face to face with their films every couple of years. But for every Kristen Stewart, there’s a Taylor Lautner — an actor who at one point was capable of causing fan pandemonium but most recently was seen in an Adam Sandler Netflix movie doing inappropriate things with a donkey.

How are the fates of young franchise stars determined?

First — and, yes, this may seem obvious — there is the matter of talent. Before Jennifer Lawrence, now 25, was cast in “The Hunger Games,” she’d already received critical acclaim and an Oscar nomination for her turn in the gritty indie “Winter’s Bone.” Shailene Woodley, 24, had a Golden Globe nod for “The Descendants” under her belt before she signed onto the “Divergent” franchise. And Stewart, who as a child costarred with Jodie Foster in “Panic Room,” has proved herself post-”Twilight” not only with the big-budget follow “Snow White and the Huntsman” (one of 2012’s top 20 films at the box office), but also with smartly chosen roles in indie movies like “Still Alice” and “Clouds of Sils Maria,” which is generating Oscar buzz for the actress.

“Kristen was a really gifted actress before she ever read ‘Twilight,’” said Nancy Kirkpatrick, who worked with the actress when she served as the head of marketing at Summit Entertainment, which made the “Twilight” films. “When she’s 50, we’re still gonna see her work.”

Just a few years ago, though, it seemed Stewart was on the verge of sabotaging her career. Tabloid stories about her tumultuous love life with “Twilight” co-star Robert Pattinson for a time overshadowed discussions about her acting. And she was so physically uncomfortable in interviews — tapping her foot, looking at the floor, mumbling — that she often came across as disengaged.

“Now I watch her in interviews and feel like I’m actually seeing the real Kristen, but that’s taken a long time,” Kirkpatrick said of the 25-year-old. “She has an amazing team and publicist. She’s practiced. But she also just grew up.”

Lawrence, however, never seemed to struggle in public. She’s the rare star who just last week seemed equally at home on National Public Radio’s “Fresh Air” with Terry Gross as she did on Andy Cohen’s Bravo talk show “Watch What Happens Live.” She hits all the aspirational BFF notes: tripping on red carpets and ordering pizzas with reporters and confessing to making out with cute costars.

But she seems to take a studied approach to her career, juggling comic book movies like “X-Men” with David O. Russell biopics. It’s obvious that she likes acting and wants to be taken seriously in Hollywood; this fall, she wrote an essay in Lena Dunham’s newsletter about wage inequality in the movie business.

Chris Pratt — who just wrapped a sci-fi love story with Lawrence — appears equally at ease with himself. Though he’d been a working television star for years, the 36-year-old became a household name only after the 2014 release of the box office hit “Guardians of the Galaxy.” Like the young stars of other Marvel and DC comic book movies — Chris Evans, Chris Hemsworth, Henry Cavill — Pratt is handsome. But the actor, who also led this summer’s “Jurassic World,” knows how to work a solid charm offensive too. You don’t just want to lift weights with him, or sleep with him — you want to grab a beer with him, or go on a double date with him and his wife, Anna Faris.

In other words, if you want to be a movie star in 2015, you have to strike a difficult balance. You have to be attractive but relatable. Goofy but disciplined. Self-effacing but self-confident.

Oh, and that franchise you’re in? It has to be good. Even though Woodley is a well-known actress, perhaps the reason she isn’t yet as recognizable as Lawrence is that the “Divergent” movies haven’t been particularly well-received by fans or critics.

That isn’t a problem for Ridley and Boyega. But for all the accolades they and the film have received, the stars should know that Walt Disney Pictures, by necessity, will promote their careers only if it helps the franchise. After all, most would argue that “The Force Awakens” grossed more than $1 billion worldwide during its first two weeks of release because of the built-in brand name value of “Star Wars” itself. Ridley and Boyega will need to find their own heroes’ journey to success in Hollywood.

Christensen, meanwhile, still considers himself lucky to have been part of a franchise with such global impact — even though it overwhelmed him at the time. After years on his Canadian farm, he’s just now finding his footing back in Hollywood at age 34.

“You can’t take years off and not have it affect your career,” he said. “But I don’t know — in a weird, sort of destructive way, there was something appealing about that to me. There was something in the back of my head that was like, ‘If this time away is gonna be damaging to my career, then so be it. If I can come back afterward and claw my way back in, then maybe I’ll feel like I earned it.’”

amy.kaufman@latimes.com

Twitter: @AmyKinLA

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