Not every Marvel Comics character has earned the live-action treatment, but one that Marvel teased early in MCU development is finally returning for his (technical) big screen debut. Marvel announced that Tim Blake Nelson will return as The Leader in the upcoming Captain America: New World Order. This won't be Nelson's first appearance in the MCU, but it will be The Leader's as the infamous villain was only teased in The Incredible Hulk.

While he's typically a Hulk villain, The Leader will undoubtedly tussle with the new Captain America. Sam Wilson has dealt with aliens, fellow heroes, and super soldiers, but nobody quite like The Leader. The Leader will challenge Sam Wilson like he's never been challenged before, but who is this green-skinned antagonist with the enlarged cranium?

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Who is The Leader in Marvel Comics?

While the Jade Giant has several notable villains, such as Abomination and Thunderbolt Ross, there's no denying that The Leader is his archnemesis. Samuel Sterns is as smart as the Hulk is strong, making for some of the most intriguing stories in Marvel comics. Seeing Hulk smash his fist into everything in sight in order to save the day is fun to read every day of the week, but seeing a good story about brain versus brawn is refreshing and exactly what the character needs from time to time.

However, he wasn't always the super intellectual villain that fans know him as. Samuel Sterns was, in fact, a high school dropout from an average family with one exception: His brother. His family showered Samuel's older brother with praise, neglecting Samuel in the process. Samuel found employment in a chemical research plant, working the night shift. One night while transporting containers of chemical waste, one of the containers spilled a lethal dose of gamma-irradiated contents onto the slow-witted Samuel Sterns.

The gamma radiation mutated Samuel Sterns instead of killing him. At first, it only transformed his mental capabilities, but his physical stature eventually changed as well. Unlike Bruce, who transformed into a mindless rage beast, Sterns became a hyperintelligent megalomaniac. Unfortunately for the world, The Leader's elevated intelligence gave him the ability to become god-like, so he created a network of spies and loyal agents dedicated to his goals for world domination and crafted weapons capable of defeating somebody as strong as the Hulk.

The Leader has evolved over the years, becoming smarter and changing his physical appearance, similar to Bruce's different Hulk evolutions. At one point, Sterns helped create the Red Hulk who in turn infected Sterns with red gamma radiation, making him the Red Leader. Despite his vast wealth of knowledge, The Leader is often his own undoing. His arrogance and obsession with defeating Hulk blind him to flaws in his plans, giving his opponents the opportunity they need to put an end to his schemes.

The Leader's Previous MCU Appearance

Audiences haven't been lucky enough to see The Leader in the MCU just yet. However, they get a glimpse at his making in The Incredible Hulk movie, starring Edward Norton. Yeah, that film many MCU fans try to forget despite it not being terrible. Throughout the film, Bruce communicates with somebody using the alias Mr. Blue. This turns out to be cellular biologist Samuel Sterns who claims to have an antidote for Banner's "condition."

After Emil Blonsky mutates into the Abomination from the same concoction meant to cure Bruce, he tosses Sterns aside, breaking a canister filled with gamma-irradiated blood. That blood spills and seeps into a laceration on the biologist's forehead. A few seconds reveals his head reacting in some way to the irradiated blood, hinting at the creation of the MCU's Leader. Unfortunately, Tim Blake Nelson's Samuel Sterns never showed up again in an MCU project, despite rumors circulating about a She-Hulk cameo.

The Leader in Captain America 4

The Incredible Hulk's ending was undoubtedly setting up The Leader for future Incredible Hulk movies, potentially even as a big bad for The Avengers. Unfortunately, due to Universal Pictures retaining distribution rights for any solo Hulk films, Marvel has been unable to further explore Hulk on his own. Thus, he appears as a supporting character in the MCU. The current rumor is that those distribution rights reverted back to Marvel, which is why The Incredible Hulk is making its way to Disney Plus, opening up the possibility to finally set up some beloved Hulk storylines.

Captain America 4's subtitle "New World Order" hints at an entity working in the shadows to manipulate the world's governments. One villain best suited for such a task is the Leader and his network of spies. Based on the events in The Incredible Hulk, Sterns has no good reason to go after Bruce just yet unless he resents being the smartest being in the world. However, he could hold a grudge against Thaddeus Ross (now played by Harrison Ford after William Hurt's passing) and the U.S. government for what they did to his lab and research.

As stated, the Leader had a role in creating Red Hulk, which might occur in Captain America: New World Order based on Ross's prominent involvement. Moreover, The Leader held a grudge against the Thunderbolts in the comics, and since Marvel is establishing them in the MCU, it may play a big role in the next Captain America film.

Director Julius Onah spoke with IGN and said:

Actions have consequences, and that's what's so great about what the MCU has been able to build. In this universe, in this world, things that people do come back in ways that are surprising and unexpected, and Tim Blake Nelson coming back as The Leader is such an exciting thing to explore because his story now is going to challenge Sam Wilson, our new Captain America, in a way that he never expected. So it's really, really thrilling. And I think a lot of things that got set up and established years ago will allow the MCU to actually go in new directions that audiences are going to really, really be excited about.

Saying "actions have consequences" sure does sound like The Leader's involvement relates to something done to him specifically, which points to Harrison Ford's Thaddeus "Thunderbolt" Ross. Especially since there's been no mention of Mark Ruffalo appearing in the film.

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