Joe Russo has warned that seeing Avengers: Endgame is "required" in order to understand Avengers: Doomsday.

A new version of the 2019 blockbuster, titled Avengers: Endgame Encore - which includes additional footage not seen in the original and a sneak peak at Avengers: Doomsday - is being released in cinemas next month and the director urged fans to buy tickets for a screening, even if they have seen the film before, because it will help "connect the story" ahead of the release of the next instalment of the Marvel Cinematic Universe (MCU) franchise this December.

Speaking to Fandango about what fans can expect from Avengers: Endgame Encore, Joe said: "It's going t o connect the story of the two movies. There's a natural progression from Endgame into Doomsday, which is also inclusive of all the other stories that have been playing out.

"But I think it's important to see Endgame again in theatres for two reasons: One, you're going to have a lot of fun cheering and screaming and reliving all the emotions you had the first time you saw it, and number two, I think it's required viewing for following the story in Doomsday."

His brother and directing partner Anthony Russo added, "If you saw Endgame when it was originally released, you couldn't see this coming."

Chris Evans has teased a "brutal" storyline for Captain America in Avengers: Doomsday.

As with all MCU blockbusters, details for Avengers: Doomsday are being kept under wraps, but Chris Evans - who will be reprising his role as Steve Rogers/Captain America - recently teased things will be "brutal" for his alter ego.

Speaking during a question and answer session at Fan Expo Boston, he said: "The Russos love beating up Steve Rogers.

"Their favourite thing to do is to just beat the c*** out of him.

"To them, that's what makes a hero, and that's someone who gets punched so many times but still gets up.

"So they keep finding new ways to kick his butt. And this one was brutal."

Last month, Hayley Atwell - who plays Evans' on-screen love interest Peggy Carter - promised fans an "existential epic" as she opened up about her role while attempting to maintain some secrecy.

She told ScreenRant: "Without giving anything away. I think that you have a movie that's an existential epic. The whole thing's turned on its head.

"It's not a world you really recognise, and then there are aspects of it that are familiar, but that feel very heightened and vulnerable.

"And I feel like, with Peggy, she's on the receiving end of that."

Peggy was last seen in Avengers: Endgame, when Steve was seen going back in time in order to live out the rest of his life alongside his one true love.

But in this film, Hayley said her character is in a "very dangerous, terrifying situation", adding: "She's hyper vigilant the whole time of the worst happening."

Hayley was then asked what kind of role Peggy takes on in the new environment, after previously being someone that everyone else can rely on.

To which she replied: "In the past, Peggy was considered the adult in the room, the one with the uniform that you can trust and rely on because she's a good person.

"It's always fun to play something that feels a little bit [more] expansive than that, a little bit more nuanced, because I think that makes her also even more human and relatable."