Natalie Portman didn't just walk back into the Marvel Cinematic Universe; she smashed the door down with a cracked hammer and biceps that put most of us to shame. For a long time, the general consensus on Jane Foster was... well, she was kinda just there. In the first two Thor movies, she was the brilliant astrophysicist who mostly existed to look worried while Chris Hemsworth hit things. Then she vanished.
People assumed she was done. Honestly, after Thor: The Dark World, it felt like the bridge had been burned. Portman is an Oscar winner. She has Black Swan and Jackie on her resume. Why would she come back to play the "girlfriend" role again?
The answer is Taika Waititi. He didn't ask her to come back as a scientist in a lab coat. He asked her to be a God.
The Jane Foster Problem: What the Early Movies Missed
If you rewatch the 2011 Thor, Portman is doing her best with the material. She’s funny, she’s curious, and she has that wide-eyed wonder. But by the sequel, the character felt stuck. In The Dark World, Jane becomes a literal vessel for an ancient sludge called the Aether. She spends half the movie fainting or being transported like a piece of luggage. It’s a waste of a talent like hers.
There were rumors for years that Portman was unhappy, especially after director Patty Jenkins—who she was excited to work with—left the project. When Thor: Ragnarok rolled around, Jane was written out with a single line about a "mutual breakup."
It felt like a quiet, somewhat unceremonious exit for a major character.
But looking back, that gap was necessary. It allowed the MCU to evolve away from the "damsel" trope. When Natalie Portman finally stepped onto the stage at San Diego Comic-Con in 2019, hoisting Mjolnir over her head, it wasn't just a gimmick. It was a promise to fix what went wrong.
Getting "Swole": The 10-Month Transformation
You’ve probably seen the photos. The ones where Portman’s arms look like they were carved out of granite. That wasn't CGI. To prepare for Thor: Love and Thunder, Portman spent 10 months training with Naomi Pendergast.
Most people don't realize how grueling this was. We're talking 4:30 a.m. sessions.
Portman is naturally petite—about 5'3". To play the Mighty Thor, she had to bulk up in a way she never had before. Her routine was a far cry from the 1,200-calorie-a-day starvation diet she endured for Black Swan. This time, it was about heavy weights, protein shakes, and pure power.
The Workout Breakdown
- Heavy Lifting: Three days a week focused entirely on the upper body (arms, chest, and back).
- Conditioning: Two days of boxing, skipping, and sprints.
- Injury Prevention: Lots of Pilates and core work to handle the weight of the suit and the stunts.
She mentioned in interviews that she’d never really tried to "get big" before. It changed how she walked. It changed her presence on set. When you see her standing next to Chris Hemsworth in the movie, she actually looks like she belongs in the same weight class.
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The Cancer Arc: Why It Mattered
One thing Thor: Love and Thunder got right was sticking to the Jason Aaron comic run. In the comics, Jane Foster is battling stage IV breast cancer. Every time she picks up the hammer and transforms into Thor, the magic purges the chemotherapy from her system. It makes her feel powerful in the moment, but it’s literally killing her faster.
It’s a heavy, dark storyline for a movie that features screaming giant goats and a character made of rocks.
Waititi balanced the "silly space adventure" with this grounded, human tragedy. Portman’s performance in these scenes is subtle. You can see the exhaustion in her eyes when the transformation wears off. It gave the character a layer of heroism that wasn't just about hitting monsters. It was about the sacrifice of being a hero when you're at your most vulnerable.
Why Some Fans Stayed Divided
Not everyone loved the return. Some felt the humor in Love and Thunder was too much, or that the tone shifted too wildly between Jane’s illness and Thor’s jealousy of his own hammer.
There’s also the "Mantle" debate.
Some fans feel like "Thor" is a name, not a title, and were frustrated with the idea of Jane taking it over. But the movie makes a point to show that Jane isn't "replacing" Thor; she's stepping up when he's lost his way. They are partners. Seeing them fight side-by-side with a reconstructed Mjolnir (which now acts like a shotgun shell of metal shards) was a high point for the franchise's choreography.
Life After the Hammer
So, what’s next? If you’ve seen the post-credits scene, you know Jane ends up in Valhalla. In the world of comic book movies, death is rarely the end, but it felt like a complete arc. She went from being a background character to a self-sacrificing legend.
Natalie Portman's journey in the Thor movies is a weird, 11-year experiment in character redemption. It took a decade, a new director, and a massive physical transformation to finally give Jane Foster the respect she deserved.
If you're looking to revisit the Portman era of the MCU, skip the "girlfriend" years and go straight to the Mighty Thor.
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Next Steps for Marvel Fans
If you want to understand the full context of Jane's transformation, read the 2014 Thor comic series by Jason Aaron. It provides a much deeper look into her internal struggle with the hammer's "worthiness" than the movie had time to explore. Also, pay attention to the small details in Love and Thunder—the way Jane tries to come up with "catchphrases" is a direct nod to her being a fan of the hero world she was once just a bystander in.