Of all the Marvel superheroes to make the jump from page to screen, Hulk has been the trickiest to get right. A modern, superhero-flavored take on the Jekyll and Hyde story, Hulk has captured the imagination of comic fans ever since his 1960s debut thanks to a distinctive green hue and uncontrollable anger issues that more or less everyone can relate to. Hulk's enduring popularity has been burgeoned by a series of live-action adaptations, the first being a 1978 TV series starring Bill Bixby (as Dr. Banner) and Lou Ferrigno (as Hulk).

A more serious, cinematic attempt at adapting the Hulk was made in 2003, with Ang Lee directing Eric Bana for the jolly green giant's first big screen outing. The film was afforded a mixed reaction, and a reboot was released five years later replacing Bana with Edward Norton in one of the earliest installments of what would later become known as the Marvel Cinematic Universe. Later in the franchise, however, Norton was recast and Mark Ruffalo became the Hulk of the Avengers movies and beyond.

Related: Keeping Edward Norton as Bruce Banner Could Have Been Better For Marvel

There's no argument that Ruffalo's Banner/Hulk is the strongest live-action interpretation of the character to date but, even so, many of the long standing difficulties in bringing Hulk to the big screen trouble Marvel to this day. Here's why adapting the Hulk is so difficult to get right.

Hulk's Character Rights Are A Mess (But Not The MCU's Problem)

Movie Hulk Immortal Thousands of Years Old

If any good has come out of the recent Spider-Man tug-of-war between Disney and Sony, it's that fans now have a clearer picture of how delicate Marvel character rights can be. The problem stems from long before Marvel Studios was producing billion dollar hits one after the other, when the comic company was verging on bankruptcy and sold the movie rights to many of their biggest characters. Now in a position to make those movies themselves, Marvel is currently working to find ways of reclaiming the likes of Spider-Man and the X-Men from rival studios. As complex as Spidey's legal ownership has proven, however, Hulk's is considerably worse.

Hulk's rights were owned by Universal, who produced the 2003 live-action venture, but after a time limit expired on making a sequel, ownership defaulted back to Marvel. Problematically, the distribution rights for any Hulk solo movies remained with Universal, and that setup remains in place to this day. Effectively, this means that Disney and Marvel Studios can't release a Hulk solo movie, because they'd be legally obliged to let Universal distribute it. Marvel's workaround for this has been to feature the Hulk only in team-up movies such as The Avengers or as a supporting character, as with Thor: Ragnarok. This is different to the Spider-Man situation, as Marvel can't use that character in any capacity without Sony's cooperation.

Not having the option of making Hulk solo movies restricts the MCU in terms of developing the character. Team-ups are always tightly-packed affairs, and the bulk of a Marvel superhero's personal growth takes place within their own dedicated series.

However, this clearly isn't the only issue behind Hulk's live-action woes. Both Universal's 2003 effort and their joint reboot with Marvel in 2008 attracted a lukewarm reception, despite being dedicated solo movies. Furthermore, plenty of figures in the MCU have thrived despite only appearing in team-ups. Black Widow won't get her first solo release until next year, Hawkeye's arc was told entirely through supporting roles and some of Tony Stark's best character moments came long after Iron Man 3. So, what else is hampering Hulk?

Related: How Thor: Ragnarok Compares To Thor And Planet Hulk Comics

Both Hulk Solo Movies Stick To The Basics (& Miss A Lot Of His Character)

Hulk destroying a city in the 2003 movie

The 1970s Hulk series is undoubtedly a cult classic but shared little in common with the comics, instead focusing on an under the radar "David" Banner trying to stay calm in a never-ending series of stressful situations. Both Hulk and The Incredible Hulk follow a similarly formulaic approach. Viewers get the origin story, the fragile dynamic between Banner and his alter ego and a cat-and-mouse chase where the hero desperately tries to avoid those who want to poke needles in him. Neither solo movie ventures far beyond that very simple premise, although the 2008 offering did attempt to introduce Abomination.

While this straightforward setup has its roots in the early The Incredible Hulk comics, it also ignores the more significant and interesting developments the character has made in Marvel's printed universe from the 1970s onward - stories that have long grown out of the big green monster vs. tank trope. These include the revelations that Bruce's past mental traumas helped create his split persona, the multiple iterations of Hulk that inhabit Banner's body and the wide selection of more fantastical adventures that make up a large portion of Hulk's comic book canon.

While it's understandable that the initial Ang Lee-directed film would seek to kick things off with a more audience-friendly approach, The Incredible Hulk's decision to retread similar ground only 5 years later created the misleading impression that the Hulk was a 2-dimensional entity only capable of smashing things, while Bruce Banner moaned about it afterwards. Perhaps the underlying issue is that Hollywood is naturally predisposed to tell a monster vs. U.S. army story than it is, say, Hulk vs. Dracula (as seen in 2011's Fear Itself storyline). While the former option might be the more obvious for big screen adaptations, it doesn't do justice to Hulk's versatility as a superhero.

MCU Hulk Is Better, But Hasn't Gone Much Further

Mark Ruffalo as Hulk in Thor Ragnarok

In the warm embrace of the MCU, Mark Ruffalo has helped craft versions of both Bruce Banner and the Hulk that are memorable and exciting to watch, while still posing interesting moral questions. New facets of the character have also been introduced, including "I'm always angry" era Hulk, a stunted relationship with Black Widow and the famous science bros. Alas, there remains a sense that the true potential of Hulk seen in the comic book is still going largely untapped.

Related: How Hulk Ends Up On Thor 3's Gladiator Planet

Perhaps the best example of this is Hulk's role in Thor: Ragnarok. While the buddy comedy material is hilarious and Hulk's dominance over Bruce Banner makes for a fascinating dynamic, Thor: Ragnarok takes elements from what is generally considered the hero's best comic story, Planet Hulk and fails to develop it. Seeing Hulk portrayed as an exiled lost soul enjoying a more savage life as a warrior on an alien planet was a huge part of the anticipation surrounding Thor: Ragnarok's release. Unfortunately, the finished movie only took superficial elements from Planet Hulk before moving onto other business, once again glossing over some of the most interesting material in Hulk's canon.

The same could be said for Professor Hulk, the version of the character seen in Avengers: Endgame. In this guise, Hulk is used to comic effect, taking selfies and making awkward faces when confronted by his far more irritable former self in 2012 New York. Although big moments would come for Hulk later in the story, the Professor Hulk material only scratches the surface of this version of the green menace, and doesn't delve into the instability of the comic iteration or the journey Banner took to reach this ideal form.

Perhaps the biggest issue with Hulk in the MCU is that the audience often sees the finished product, but not how Hulk got there. In The Avengers, Banner has already learned to control his transformation, in Thor: Ragnarok, Hulk is the Green Scar of Sakaar at the beginning of the film and in Avengers: Endgame, Professor Hulk arrives fully formed, having already balanced his two personalities off-screen. Without seeing what occurred in between these phases, it's hard to invest as much in Hulk as the audience does in the likes of Tony Stark and Steve Rogers.

What Marvel Can Now Do With Hulk

She-Hulk

With the MCU's recent expansion onto the Disney+ streaming service, Marvel now has an opportunity to take Hulk, or at least the concept of Hulk, into some varied and creative new directions. She-Hulk has been confirmed as appearing both in her own solo series and as a part of the wider franchise, opening up a host of new opportunities for the MCU's green and muscular contingent. It's not currently known to what extent (if at all) Mark Ruffalo's Hulk will feature alongside She-Hulk or how this would factor into the character's ownership situation, but regardless of whether or not the original Hulk appears, the path is set to adapt some previously unexplored areas of Hulk's comic book mythos.

Related: How Every Disney+ Show Will Connect To The Marvel Movies

The very existence of She-Hulk in the MCU will necessitate some character development on Bruce Banner's part, especially if her recognized blood transfusion origin story is used. How will Hulk react to afflicting his own cousin with his vilified condition? Will he mentor She-Hulk, or be jealous that her transformation is easier to control?

Additionally, the Jennifer Walters character lends itself more naturally to smarter storytelling, rendering the Hulk vs. tank premise of yesteryear moot. Walters' public career as a lawyer, her decision to permanently adopt her alter ego and the heroine's initial drive for vengeance all offer compelling, unique story options that the Hulk himself has yet to be afforded in his live-action form.

More: The MCU Isn't Honoring Hulk For Reversing Thanos' Snap - Why?

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