Jane Foster’s cameo in Avengers: Endgame was so brief that Natalie Portman didn’t even need to film any new scenes for it. Instead, co-directors Anthony and Joe Russo used old footage from 2013’s Thor: The Dark World, though the actress was still called on to do a little voice work. In an early version of the script, however, it seems that the God of Thunder’s ex was given a lot more screen time opposite both Thor himself and his little raccoon companion.
Speaking at San Diego Comic-Con, Endgame co-writer Christopher Markus explained that they scripted a reunion between Chris Hemsworth’s character and Jane, but ultimately felt that a scene opposite Thor’s mother would be more appropriate for the hero’s arc:
“Once we figured out the sort of track we wanted Thor to be on, that he was really going to crumble — as any of us would, probably — that the only person who could put him together [would be Frigga]. We wrote a scene with him and Jane, but Jane isn’t the person to put him back together. Odin is not the person to put him back together. Really, it only is his mother.”
Once it was decided that Thor would share the screen with Frigga, his reunion with Jane was written out for the sake of pacing and logistics:
“[W]e couldn’t have him run, get the stone, then go talk to his mom — it would take a disproportionately amount of time. Plus, we never know how the Aether turns into a stone, no one’s ever seen it happen, it just happens.”
Ultimately, the writers settled on Rocket as the one to extract the Reality Stone from Jane, and according to co-writer Stephen McFeely, it was considered more tasteful to have the Guardian carry out his mission off-screen:
“It seemed for decorum, that maybe getting it out of Jane Foster was better left offscreen.”
That being said, the writers also threw around the idea of Rocket earning Jane’s cooperation by appealing to her scientific background, though as Markus recalled, the idea was eventually dropped in order to keep the runtime down:
“It was very satisfying, and I thought everybody came off well in it. But we had a three-some-hour movie, and some things are better left [out].”
In the end, Jane’s presence in Avengers: Endgame was pretty minimal, though as you’ve likely heard by now, Marvel still has big plans for Portman, which we’ll see come to fruition when Thor: Love and Thunder hits theaters on November 5th, 2021.