Of all the Avengers to undergo changes over the course of Avengers: Endgame, perhaps none were as outwardly drastic as Thor's change in physique.

Consumed by guilt after failing to kill Thanos at the end of Avengers: Infinity War and prevent him from wiping out half of all life in the universe with the Infinity Gauntlet, Thor spends the subsequent five years letting himself go physically, gaining considerable weight. Endgame co-star Mark Ruffalo has shared a behind-the-scenes photo of actor Chris Hemsworth napping between filming scenes after the character's transformation.

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Based on the photo, the scenes being filmed appear to be for the surviving Avengers mourning the death of Black Widow, who had sacrificed herself on Vormir so that Hawkeye could obtain the Soul Stone.

With an unkempt wig, scruffy beard and fat suit, Hemsworth is relaxing between shooting scenes for the emotional sequence, his script pages still visibly in his hands.

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Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos. The film is in theaters now.