Avengers Endgame: This is the REAL reason behind THAT Thor twist 'It's really surprising'

WARNING: Spoilers for Avengers Endgame ahead.

The Marvel all-star smash sees a five-year time jump, after some of the surviving Avengers track down and murder Thanos (Josh Brolin).

When we join them half a decade later, Thor (Chris Hemsworth) has lost his God of Thunder physique and has gained weight.

He spends his time holed up in a downtrodden house in the village of New Asgard, drinking alcohol and playing videogames.

The so-called “fat Thor” point has been criticised by some, with backlash over the jokes some other characters make at his expense.

However it has also been praised for showing a feasible result of the huge trauma the character would be facing.

In a new interview, co-director Anthony Russo has explained the thinking behind Thor’s physical transformation.

“[Hemsworth] was on board,” he told The Hollywood Reporter. “We talked to him early on about it.

“That was born from us just thinking about, on an individual level, how each of the Avengers were moving forward from the moment at the end of Infinity War.

“How they were dealing with the pain of having lost to Thanos and the pain of losing everyone? We just started building.

“This came out of really intense sessions with the writers, Markus and McFeely.

“We just started circling this character, who was really blaming himself.”

He added: “If you look at the loss Thor suffers in Infinity War, it’s staggering.

“From the beginning of the film, when Thanos attacks his ship, kills Loki and Heimdal and much of his people. And all the way through to his failure to stop Thanos.

“We started thinking about how that would weigh on him and what that would do to him.

“We started circling this idea of depression and throwing that out in a way that we thought was really surprising and interesting.

Ultimately, though Thor begins to reconnect with himself in the movie, he does not return to his previous physical state – something that has also been praised by critics and commentators.

It’s unclear where Hemsworth’s character goes from here, though the end of the movie hints towards adventures with the Guardians of the Galaxy.

Meanwhile, the Russos have revealed that Robert Downey Jr had “mixed” emotions over Iron Man’s ending.

Avengers: Endgame is out now.