In the early days of Marvel Studios, no one could have predicted the impact these films would have. In fact, the studio originally planned for 2012's The Avengers to be the last film in the franchise that began with 2008's Iron Man. 

"For the longest time, Avengers was our horizon line, what we were aiming for," Marvel Entertainment Chief Creative Officer and Marvel Studios President Kevin Feige told THR.

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Marvel Studios would go on to be bought by Disney in 2009 after the release of the first Iron Man film -- a move Feige described as "the greatest thing that ever happened to us."

The Marvel Cinematic Universe is now comprised of 23 released films. Phase Three of the franchise ended in 2019 with Spider-Man: Far From Home and Phase Four is set to begin next year which such offerings as Black Widow, Shang-Chi and the Legend of the Ten Rings and Eternals, among others. What's more, a number of Marvel series are set to premiere on the Disney+.

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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 as Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie, and Josh Brolin as Thanos. The film is now available on Digital HD, Blu-ray and 4K UHD.