There's no denying the Marvel Cinematic Universe is one of the biggest cinema franchises of all time. With 27 feature films raking in over $27 billion worldwide and a plethora of live-action and animated series under its belt, it's almost shocking to think that what started as a small comic company has exploded into the expansive multiverse of properties that it is today. Over a decade after its inception, Marvel Studios continues to pump out superhero flicks featuring iconic characters like Captain America and Thor, rejuvenating these heroes and translating them from page to screen effortlessly. At this rate, it seems as though Marvel has a formula for crafting a blockbuster of a movie, though it's also nice to look back on the more humble beginnings of the MCU.

Though many credit 2008's Iron Man as the start of the MCU proper, there's one film that some Marvel fans would rather leave out of the lineup altogether, despite its importance in the MCU timeline. Though not technically considered part of MCU canon, The Incredible Hulk was one of the first movies to introduce characters that would later join the iconic Avengers team several years downline. Starring Ed Norton as Bruce Banner, The Incredible Hulk is a sub-par origin story of a scientist seeking a cure for an experiment gone wrong that drastically changed his quality of life.

This article has been updated to correct a factual error involving release dates.

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incredible hulk

Now afflicted with a condition that turns him into a raging green monster with a massive spike in heart rate, The Incredible Hulk is filled with solid action sequences and an easy-enough-to-follow storyline paired with pretty decent special effects considering the time it was made. Over the course of the film, Banner interacts with several characters that later reprise their roles in the MCU, including the late William Hurt as Secretary of State Thaddeus Ross.

Ross, as a government figure in the MCU, butts heads with his super-powered colleagues and even plays a huge role in Captain America: Civil War by introducing the Sokovia Accords to the Avengers, which ultimately divides them. Prior to his death in March 2022, many Marvel fans had speculated some live-action form of the Thunderbolts would make their way to the MCU, following Ross' storyline in Marvel Comics. While Hurt won't be around to see this particular storyline come to fruition, it's still possible that the Thunderbolts will make an appearance, as several hints pointing toward their formation have already appeared in recent Marvel titles.

While Ross' inclusion in The Incredible Hulk gave no intimation of his future in the MCU, a cameo in the end-credits scene officially changed the game for superhero films to come. The amazing and shocking appearance of Robert Downey Jr. as Tony Stark in the final moments of The incredible Hulk served as a hint of what was in store for the future of Marvel Studios. Iron Man, which debuted in theaters earlier that same year, would go on to become what many truly claim as the start of the Marvel Cinematic Universe, with Downey's performance being hailed as the highlight -- and heart -- of the MCU for over a decade, securing him as the most powerful Avenger in many a Marvel fan's eyes.

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Bruce Banner smiles with green eyes in The Incredible Hulk

Another character in The Incredible Hulk that has made a more recent MCU appearance was Tim Roth, who played Banner's adversary Emil Blonsky/The Abomination. While the ultimate showdown between The Hulk and Abomination was anticlimactic at best, Abomination did make a brief appearance in one of the most recent Marvel films, Shang-Chi and the Legend of the Ten Rings. Roth is also set to appear in the upcoming Marvel Disney+ Series She-Hulk, meaning Marvel fans may see him pop up in the MCU again, sooner rather than later.

Was The Incredible Hulk a perfect film? Not by any means, though it did have the building blocks needed to grow the Marvel Cinematic Universe as fans know it today. By introducing recurring characters like Thaddeus Ross, Emil Blonsky and, of course, Tony Stark, the replacement of Ed Norton as Bruce Banner was easy to overlook, as the resulting products not only succeeded in building and sustaining a cinematic powerhouse, it secured Marvel Studios as a film staple for decades to come.