In a Q&A session held Wednesday after a special screening of Avengers: Infinity War, directors Joe and Anthony Russo pointedly said they wouldn't discuss anything about the upcoming sequel, they did offer more details about the unexpected appearance of Red Skull in their 2018 blockbuster.The classic Marvel Comics villain made his big-screen debut in 2011's Captain America: The First Avenger, where he was played by Hugo Weaving. Red Skull seemingly died at the end of that film in an explosion by the Tesseract (also known as the Space Stone), only to make a surprise cameo during a pivotal scene of Infinity War. However, he wasn't played by Weaving but instead by Ross Marquand of The Walking Dead.RELATED: Infinity War's Red Skull Actor Won't Say Whether He's in Avengers 4The Russo were asked about the re-casting during the Q&A session, and Slashfilm's Peter Sciretta transcribed some key points to Twitter:

Marquand's performance hewed close enough to the original that many viewers didn't immediately realize there had been a cast change. Weaving had reportedly grown tired of the process involved in making huge franchise films after having participated in multiple series -- including The Matrix, The Lord of the Rings and The Hobbit -- and had expressed little desire to return to the Marvel Cinematic Universe. Now we know he was asked to reprise his role as Red Skull, but bowed out.

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There are still few details known about Avengers 4, including whether we will see Red Skull return. Now that the Soul Stone has been turned over to Thanos, there may be no need to revisit Red Skull's story arc, but given what a surprise his reappearance was in Infinity War, and how shrouded in mystery the list of returning actors remains, fans can never be too quick to rule anything out.

Marvel Studio's untitled fourth Avengers film will premiere worldwide May 3, 2019. Directed by Joe and Anthony Russo, the film stars Robert Downey Jr., Josh Brolin, Mark Ruffalo, Tom Hiddleston, Chris Evans, Chris Hemsworth, Chadwick Boseman, Jeremy Renner, Chris Pratt, Scarlett Johansson, Elizabeth Olsen, Tom Holland, Sebastian Stan, Anthony Mackie, Benedict Cumberbatch, Paul Bettany, Samuel L. Jackson, Cobie Smulders, Benedict Wong, Zoë Saldana, Karen Gillan, Dave Bautista, Pom Klementieff, and Vin Diesel.

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