'Avengers: Endgame' Used Never Before Seen Footage From 'Thor: The Dark World' For A Key Time Travel Sequence, Including Natalie Portman's Appearance

It turns out Natalie Portman didn't have to set foot on the "Avengers: Endgame" set to be a part of one of the biggest box-office hits of all time.

Portman reprised her role as the astrophysicist Jane Foster from the first two "Thor" movies very briefly in "Endgame," when Thor and Rocket go back in time to retrieve the Aether Infinity Stone.

The two Avengers' time-travel journey brings them to Asgard at the same time Foster (Portman) is on the planet during the events of 2013's "Thor: The Dark World."

In one scene, we see Thor (Chris Hemsworth) and Rocket (voiced by Bradley Cooper) sneak past Loki (Tom Hiddleston) while he's a prisoner in a cell. Later, we see a shot of Foster before Rocket gets the Aether out of her off camera. (Earlier in "The Dark World," Foster was infected by the Aether.)

Tom Hiddleston as Loki in "Thor: The Dark World."

According to Jeffrey Ford, an "Endgame" coeditor, both shots were from unused footage from "The Dark World."

"The shot of Loki throwing his cup in the cell and Thor and Rocket sneak past him in the background, that's a piece of digital negative taken from the dailies of 'The Dark World' that we repurposed," Ford told Business Insider. "The same for the scene of Natalie Portman."

'Avengers: Endgame' used never-before-seen footage from 'Thor: The Dark World' for a key time-travel sequence, including Natalie Portman's appearance
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