WEST HOLLYWOOD, CALIF. — Margot Robbie came racing into the tucked-away bungalow she was renting here. She had returned from recording the voice of a talking dingo for a DreamWorks animated movie, and on an April afternoon was doing her best to clean up strewn clothes from overstuffed suitcases — evidence that an intended one-week visit to Los Angeles had stretched into a month.
“I’m sorry it’s so manic,” said this 25-year-old actress, who was born in Gold Coast, Australia, and lives in London, yet had not seen either city in a very long time.
“I’m always like, ‘No, it will calm down next week,’” she said in a more relaxed moment, stretched across a patio couch next to a faded pillow that said “God Save the Queen.”
“And then the following week ends up being crazier.”
Ms. Robbie was on the latest leg of the globe-trotting journey that has consumed her since 2013. It began at roughly the moment that a worldwide audience discovered her in Martin Scorsese’s “The Wolf of Wall Street,” playing the no-nonsense lover-turned-wife of an unscrupulous broker played by Leonardo DiCaprio.
After three years of relentless film work, she is poised for two of her most prominent roles this summer, in franchise movies whose success could transform her from a wannabe to a deserves-to-be star.
First, she’ll be seen as a self-reliant and decidedly un-dainty Jane in “The Legend of Tarzan,” a new adventure of that jungle hero opening July 1. Then, on Aug. 5, she stars in “Suicide Squad,” based on the DC Comics series, as Harley Quinn, a cracked-up criminal psychologist who wields a baseball bat and a Brooklyn accent with equal ferocity.
These prospects would sound like an actor’s dreams come true, yet they have prompted Ms. Robbie to wonder if they are indeed the fulfillment of her aspirations.
While taking care not to sound ungrateful, she is openly wrestling with what it means to be so visible and whether this was quite what she envisioned doing at this stage of her career.
“It’s always a hustle,” she said. “I thought it would be a mountain, where you get to the top, and then it’s like: ‘Wheeee! It’s so easy after this.’”
Instead, Ms. Robbie said: “Any time I get near the top, I’m like, ‘There’s another mountain!’ The hustle continues.”
The third of four siblings raised by a single mother, Ms. Robbie has been in almost perpetual motion since the end of 2010, when her contract ended on “Neighbours,” an Australian soap opera on which she played a free-spirited bisexual woman in search of her biological father.
Within days, she was on a plane to Los Angeles seeking representation and auditions for American TV pilots. She was quickly cast in the ABC period drama “Pan Am.”
“It’s so much more fun for people to describe it as winning the lottery and the overnight sensation,” she said. “But it was all very strategic: These are the steps that need to be accomplished.”
The cancellation of “Pan Am” after just 14 episodes was actually a lucky break, allowing her to take roles in Richard Curtis’s romantic comedy “About Time” and then “The Wolf of Wall Street.”
Her formidable performance (and Noo Yawk dialect) in “The Wolf of Wall Street” became her calling card. But it also required her to appear in several nude scenes, including one in which she entices Mr. DiCaprio’s character wearing only a pair of stockings and high heels.
Ms. Robbie said she struggled with that provocative sequence. Recalling her thoughts at the time, she said: “The sacrifice I have to make is that I have to do this nudity thing that I don’t really want to do. But I get to work with Scorsese, which I really want to do. O.K., what outweighs what?”
Though the director told her she could play the scene in a robe or underwear, Ms. Robbie said that once she got invested in the character: “I was like, she wouldn’t do that, no way. She would be fully naked.”
Since then, Ms. Robbie has starred in “Suite Française” (adapted from Irène Némirovsky’s fiction) and the comic con-artist thriller “Focus” (with Will Smith).
But it is “The Wolf of Wall Street” that filmmakers keep coming back to and casting her from.
David Yates, the director of “The Legend of Tarzan,” said that seeing Ms. Robbie in that film made her look “glamorous and exciting” but also caused him to wonder, is she “going to be a flavor-of-the-month thing”?
The director (whose credits include four “Harry Potter” films as well as the coming “Fantastic Beasts and Where to Find Them”), said that for his “Tarzan,” he consciously avoided creating a Jane “that felt too vulnerable, that needed rescuing.”
Meeting Ms. Robbie, Mr. Yates said, revealed a woman who was right for the part but different from what he expected.
“She’s very pragmatic,” he said. “She’s quite insightful. Despite the fact that she looks wonderful and she’s quite ambitious in a good way, she has her feet on the ground.”
For Ms. Robbie, “Tarzan” called for a lot of time in front of green screens in London, pretending to run from animal stampedes or endure a monsoon.
(In the midst of filming, she celebrated her 24th birthday with a 24-hour-long party. “So many people were like, ‘Margot, I’m tired,’” she said. “I’m like, ‘We’re not done yet!’”)
She faced a different kind of endurance contest preparing for “Suicide Squad,” whose cast also includes Mr. Smith and Jared Leto, and in which Ms. Robbie is one miscreant on a team of mismatched villains-turned-heroes.
From his first Skype conversation with Ms. Robbie, the film’s writer-director, David Ayer (“End of Watch,” “Fury”), said, “she was a very analytical and serious person.” He added, “But once she feels comfortable, she really opens up.”
That was the actor Mr. Ayer said he wanted for the unhinged Harley Quinn, who could bring to life the character’s “gear shifts, the wild forays and suddenly can be real and heartbreaking.”
As Harley Quinn, Ms. Robbie once again had to put much of her body on display: The character almost always wears tiny shorts and is seen, in one trailer, changing into a tight T-shirt. Ms. Robbie said she could justify the wardrobe: Her character is “wearing hot pants because they’re sparkly and fun,” she said, not because “she wanted guys to look at her ass.”
But, she added: “As Margot, no, I don’t like wearing that. I’m eating burgers at lunchtime, and then you go do a scene where you’re hosed down and soaking wet in a white T-shirt, it’s so clingy and you’re self-conscious about it.”
Mr. Ayer said that “I didn’t think denim overalls would be appropriate for that character” and that Ms. Robbie understood “that’s part of the iconography.”
Ms. Robbie said that when she is playing characters who are confident about their appearance — say, a self-assured war correspondent in the Tina Fey comedy “Whiskey Tango Foxtrot” or a satirical version of herself, explaining subprime mortgages from a bubble bath in “The Big Short” — she is not necessarily feeling that way.
“You need to act like you think you’re really gorgeous,” she said, “and you need to be completely convinced with that, because everyone else will believe it, too.”
Ms. Robbie said she can do that “when I’m really sure it’s not me.”
Should there be a “Suicide Squad” sequel, she said, half-jokingly and half not, “I’m not wearing hot pants next time.”
Her “Suicide Squad” co-stars described Ms. Robbie as a performer whose tenacity gets overlooked in a superficial glance.
“You might be fooled into thinking she’s such an easygoing person, but she’s very, very serious about what she does,” said Jai Courtney, a fellow Australian who plays Captain Boomerang.
“Her pursuit for it has been carried out doggedly,” he said. “She deserves it. She’s worked for it. But she’s also not resting on any laurels or gifts or physical attributes.”
Already, Ms. Robbie has helped create a new production company, LuckyChap Entertainment, to develop projects she could potentially star in, like a planned film about Tonya Harding, the disgraced Olympic figure skater.
Getting into producing, she acknowledged, was also a way to leverage her fame willingly before others can exploit it.
“It took a little while to get my head around the fact that, oh, you’re a commodity now, and there’s a value placed on your head,” she said. “Someone’s always going to be using your name, milking that and taking advantage of it. So you might as well let your friends do it.”
Asked if she felt she had achieved what she hoped for when she first came to Hollywood, Ms. Robbie thought for a moment before answering no. She couldn’t quite say what she wanted then but described a flight of fancy that had lately crossed her mind.
“Often I’m like, ‘I should’ve been a stuntwoman,’” she said. “I love doing stunts and being on set, but then you wouldn’t have to be famous.”
But then, she said, “You can’t really turn back the clock.”
