Is The Incredible Hulk really part of the MCU? That's a question that Marvel fans have been asking for over a decade at this point, and while it's certainly one of the most removed entries in the series, the sheer number of references to the movie in later Marvel Cinematic Universe prove how important it is.

Distributed by Universal at a time when Paramount handled the MCU, starring Edward Norton as Bruce Banner in a riff on the 1970s TV series of the same name, and teasing Tim Blake Nelson's The Leader as a villain in a sequel, it's not hard to see why so many feel The Incredible Hulk isn't part of the rest of the Marvel canon. It's very much a product of its time - both in terms of the Hollywood landscape and how early Marvel Studios worked - and doesn't gel well when doing a full franchise rewatch.

Related: The MCU Didn't Have A Good Plan At First - And Incredible Hulk Proves It

But that would be missing the multitude of references to The Incredible Hulk throughout the following MCU movies that canonize the movie and keep it somewhat relevant (or as relevant as a Phase 1 movie that can't get a sequel due to character rights reasons). Here's every time the MCU referenced Edward Norton's Hulk.

The Avengers References The Incredible Hulk's Deleted Opening

In The Avengers, when the team begins to argue (under the influence of Loki's scepter/the Mind Stone), Banner challenges Fury's plan to put the Hulk in a cage and states that attempting to kill him will be fruitless: "You can't! I know! I tried! I got low. I didn't see an end, so I put a bullet in my mouth and the other guy spit it out!" It's a pretty dark moment for an otherwise light-mannered film that effectively provides a key clue to Bruce Banner's mental state, but also nods to a deleted scene from The Incredible Hulk.

The movie as released begins with Bruce hiding out in Rio de Janeiro, Brazil, but it originally started in the Arctic. An alternate opening saw Bruce travel north into complete isolation to try and kill himself, shooting himself in the mouth only to transform into the Hulk and break an ice shelf. The Avengers line would appear to be Joss Whedon nodding towards that, although that doesn't mean the deleted scene itself is canon; it also features a blink-and-you'll-miss-it glimpse of Steve Rogers frozen in the ice, which contradicts how he's found in Captain America: The First Avenger.

Mark Ruffalo References The Incredible Hulk's Finale

Hulk in Harlem in The Incredible Hulk

Years before the Battle of New York had Earth's Mightiest Heroes fighting aliens in Manhattan, The Incredible Hulk saw the green goliath duke it out with Abomination in Harlem (the exact number of years is iffy - the movie released four years earlier, but the currently accepted timeline has that event only one year prior).

Read More: A Complete History Of The Marvel Cinematic Universe

This event is again referenced by Ruffalo's Banner in The Avengers. Tony Stark invites his new Science Bro to visit Stark Tower in NYC, to which Bruce responds, "Thanks, but the last time I was in New

York I kind of broke... Harlem." Assuming this is just a year ago, the regret of that encounter must be quite raw.

The Avengers Reiterates The Hulk's Captain America Connection

Edward Norton plays Bruce Banner in The Incredible Hulk

The origin of the Hulk in the MCU takes its inspiration from the Ultimate comics; it's still an experiment gone wrong, but in this case one specifically tied to Captain America. The US military was attempting to replicate the super soldier serum that gave Steve Rogers superpowers, with gamma radiation seemingly replacing the "vita-rays". Bruce Banner decided to test his version on himself, and the rest is tortured history.

Captain America: The First Avenger deepened this by explaining how Dr. Erskine was killed straight after Captain America's creation, meaning knowledge of the serum died with him, and then in The Avengers this connection was solidified; Bruce was introduced to Steve as an attempted successor.

The Consultant Helped Tony Stark's Incredible Hulk Cameo Make Sense

Tony Stark talking to Ross in The Incredible Hulk

Obviously, the biggest direct connection between The Incredible Hulk and the rest of the MCU is its post-credits scene (which actually comes straight after the main story), where Tony Stark visits a drunk General Ross to discuss a team he's putting together. It's a direct tease for The Avengers, the only problem being that it doesn't make any sense in the accepted Phase 1 timeline: at this point, Tony had been removed from consideration for the Avengers Initiative (Iron Man 2 takes place alongside Hulk per an Easter egg in the final scene).

Related: Everything We Know About Hulk's Role In Avengers: Endgame

This was explained in Marvel One-Shot The Consultant, which saw Agents Coulson and Sitwell discuss how they would use Stark's abrasive personality to trick Ross into keeping Abomination locked away. It's a lot of effort to go to in explaining a continuity misstep (later movies would either ignore them outright or play it off as a joke), and goes to show just how valuable The Incredible Hulk was to Marvel once upon a time.

Hulk Was Always Angry

But all of what's been discussed is flavor to an unavoidable fact: The Avengers directly continues The Incredible Hulk's story. In the team-up, Bruce has a big secret regarding his alter-ego that he holds back until the Battle of New York: he's "always angry" and is able to turn into the Hulk at will. This was a major deviation from the commonly accepted view of the character (but a point the comics had reached decades before) and opened up new storytelling avenues for the beast.

Of course, fans who were paying attention would have known this before Mark Ruffalo even turned up. The Incredible Hulk ends with Bruce meditating and willingly pushing his heart rate up to bring the Hulk out, implying he's gaining control (something stated more explicitly in the novelization).

Page 2 of 2: Returning Incredible Hulk Characters In The MCU

Thunderbolt Ross appears in Captain America: Civil War.

General Ross Returns In Captain America: Civil War & Avengers: Infinity War

The biggest knock to The Incredible Hulk's MCU connectivity for many years was the fact none of the actors returned; most were written out and Ruffalo replaced Norton. In fact, it was a whole eight years before anybody appeared. William Hurt reprised his role of Thaddeus Ross in Captain America: Civil War, now United States Secretary of State after retiring from the military following a heart attack. He proved instrumental in passing the Sokovia Accords and forcing Cap's team underground. He later returned in Avengers: Infinity War, where Rhodey rejected his authority in the face of Thanos' threat.

Related: Thor: Ragnarok Wastes Bruce Banner

This is a rather weird return, though. While Hurt's Ross in Civil War is undoubtedly the same character, he doesn't pay much attention to Bruce Banner when discussing how the Hulk and Thor are missing, nor does his demeanor quite match up.

Martin Starr Returned In Spider-Man: Homecoming

Incredible Hulk Martin Starr Spider-Man Homecoming Role Theory

William Hurt may not be the only actor who returned from The Incredible Hulk in a later MCU movie. Martin Starr had a brief cameo in the 2008 film as a computer nerd at Culver University, and nine years later played Peter Parker's teacher Mr. Harrington in Spider-Man: Homecoming. It's distinctly possible that Starr is playing the same characters in both.

Of course, this is at present just a fan theory and a result of Jon Watts not wanting to let a previous bit part get in the way of casting a secondary role, but Starr's parts could definitely be retconned similar to Peter Park in Iron Man 2.

Theory: The Incredible Hulk Has A Spider-Man: Homecoming Cameo

Betty Ross Died In The Snap

Liv Tyler as Betty Ross from The Incredible Hulk

None of the MCU love interests, with the arguable exception of Pepper Potts and Peggy Carter, get much of a fair shake in the movies, but none have come out of it worse than Liv Tyler's Betty Ross. She was integral to Bruce's arc in The Incredible Hulk, yet hasn't been mentioned at all since in the movies, with Banner now linked to Black Widow (the most has been a couple of nods to Betty in prelude comics). Even Jane Foster got a cursory wink in Avengers: Age of Ultron.

Betty has been discussed in the wake of Infinity War, although the results aren't good. While confirming who did and didn't survive Thanos' snap at the end of the film, the Russo brothers stated that Betty was turned to dust. Whether or not she and Bruce will get a reunion when it's undone in Avengers: Endgame is uncertain, but don't hold your breath.

Next: What Is Hulk's Future In The MCU After Avengers 4?

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