Jane Foster is a fictional character in the film and television franchise Marvel Cinematic Universe (MCU) portrayed by Natalie Portman, based on the character of the same name from Marvel Comics created by Stan Lee, Larry Lieber, and Jack Kirby.
Foster appears in Thor (2011), Thor: The Dark World (2013), and Thor: Love and Thunder (2022), where she becomes the Mighty Thor. Alternate versions of Foster appear in Avengers: Endgame (2019) and the animated television series What If...? (2021).
Although Portman's performance was praised, the character received mixed reception from the first two Thor films, though her portrayal in Thor: Love and Thunder as the Mighty Thor was better received and is considered by many to be one of the highlights of the film.
Concept and creation
The comic book character, Jane Foster, first appeared in Journey into Mystery #84 (September 1962), and was created by plotter Stan Lee, scripter Larry Lieber and penciler Jack Kirby. Named "Jane Nelson" in her first two appearances, she went on to appear as the love interest of Dr. Donald Blake, the secret identity of the Norse god superhero Thor, in nearly every issue through #136 (Jan. 1967) of the title, by then renamed Thor.
Natalie Portman was cast as Foster in July 2009. When asked why she took the role for Thor, Portman replied, "I just thought it sounded like a weird idea because Kenneth Branagh's directing it, so I was just like, 'Kenneth Branagh doing Thor is super-weird, I've gotta do it. On October 13, 2011, Marvel confirmed that Portman would return to star in Thor: The Dark World. Her role as the character in Thor: Love and Thunder was confirmed in July 2019, as well as a storyline including her becoming the character Mighty Thor.
Characterization
Portman stated that she really wanted to do a big effects film that emphasized character, and getting to do it with Branagh was a new way of approaching it, relative to Star Wars. Regarding her preparation for the role Portman remarked, "I signed on to do it before there was a script. And Ken, who's amazing, who is so incredible, was like, 'You can really help create this character'. I got to read all of these biographies of female scientists like Rosalind Franklin who actually discovered the DNA double helix but didn't get the credit for it. The struggles they had and the way that they thought – I was like, 'What a great opportunity, in a very big movie that is going to be seen by a lot of people, to have a woman as a scientist'. She's a very serious scientist. Because in the comic she's a nurse and now they made her an astrophysicist. Really, I know it sounds silly, but it is those little things that makes girls think it's possible. It doesn't give them a [role] model of 'Oh, I just have to dress cute in movies'".
Speaking to the character's role in Thor: The Dark World, producer Kevin Feige said, "[W]hile Thor was a fish out of water on Earth in the first two films (Thor and The Avengers), this time Jane is very much a fish out of water in Asgard." Portman added, "It was a whole different adventure this time. Because Jane is the fish out of water. I didn't want to make it like Bill & Ted, or like a valley girl dumped into Shakespeareland." Portman also said the film finds Jane at a different place in her life, "Jane has moved, so she's now in London, not in Santa Fe anymore. Obviously she has gone through missing Thor and also being upset at him because he didn't come knock on her door when he was on her planet. She's definitely been getting over that and trying to move on." Hemsworth's wife Elsa Pataky stood in for Portman during the post-credits kissing scene due to a scheduling conflict.
In Thor: Love and Thunder, Foster is undergoing cancer treatment while becoming the superhero the Mighty Thor, gaining a costume and powers similar to Thor's due to wielding a reconstructed version of his hammer Mjolnir. Portman, who did not appear in the previous film Thor: Ragnarok (2017), agreed to return after a meeting with director Taika Waititi, who said Foster's return to Thor's life after eight years would be a big adjustment for him since she has had another life without him. Waititi added that Foster showing up dressed like Thor would be a "real mindfuck" for him. In preparation for the role, Portman took the Mjolnir prop home to practice using it for her stunts.