Despite not being seen or heard from since Phase 1 of the MCU, one of Marvel's most terrifying and sinister villains is set to return in Phase 5's Captain America: Brave New World. Brave New World will mark Anthony Mackie's theatrical debut as the MCU's new Captain America, after he became the star-spangled hero in The Falcon and the Winter Soldier, assuming the role from the retired Steve Rogers. Scheduled for release on July 26, 2024, Captain America: Brave New World's cast features several returning characters, two of whom are making their first appearances in the MCU since 2008's The Incredible Hulk.

It's been suspected that Sam Wilson will go toe-to-toe with the Serpent Society in Captain America: Brave New World, a villainous organization with ties to the likes of HYDRA, Kingpin, and AIM. While this, and Wilson's strained relationship with the new President of the United States, Harrison Ford's Thaddeus Ross, will be key to Captain America: Brave New World's storyline, the Phase 5 film is also bringing back one powerful villain who was first teased in 2008. Bruce Banner's first MCU adventure saw him working with Dr. Samuel Sterns to cure him of the Hulk, but this led to the creation of potentially one of the MCU's most formidable foes.

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Samuel Sterns' Leader Was Set Up In The Incredible Hulk

Tim Blake Nelson debuted as Samuel Sterns in The Incredible Hulk, using the alias "Mr. Blue" for his communications with Bruce Banner. Sterns was fascinated with the Hulk, but helped Banner to seek a cure for his infliction, even going so far as to synthesize Banner's blood to run a number of tests. Sterns' cure might have failed, but he did go on to create the Abomination by infusing Emil Blonsky with Banner's blood, and during the Abomination's initial attack, Sterns himself was injured. When an open wound on Sterns' head was exposed to Banner's blood, his head began to grow and transform, teasing his eventual return as the Leader.

Why The Leader Is Unlike Any Other MCU Villain

In Marvel Comics, Sterns was a janitor who was exposed to gamma radiation, transforming him into a green-skinned, super-intelligent being who named himself the Leader and became hell-bent on world domination. He is one of the Hulk's most sinister and prevailing villains, regularly using his incomprehensible intellect to battle Bruce Banner. While his massive intelligence is perhaps his most memorable ability, the Leader also has the strength and durability of the Hulk, and has unlocked latent telekinetic and telepathic powers in himself, making him able to control the minds of others through skin-to-skin contact, create illusions, and wipe mind-wipe any human he sees fit.

In Marvel Comics, the Leader's intellect is so massive that he can predict probabilities to such a high degree that he can see the future, which could make him an almost unstoppable villain for Sam Wilson's Captain America in the MCU. Sterns hasn't been seen or mentioned since The Incredible Hulk, but Tim Blake Nelson will reprise the role in Brave New World, returning as the Leader. Sterns may have been an ally to Bruce Banner, but the Leader will be anything but friendly when he crosses paths with Sam Wilson, and he could even have a pivotal role in transforming Thaddeus Ross into the MCU's rumored Red Hulk.

The MCU Should Keep The Leader Alive After Captain America 4

Samuel Sterns' return in Captain America: Brave New World is exciting, as he has been a constant thorn in the Hulk's side in Marvel Comics. For this reason, the Leader should become a consistent fixture in the MCU's future, as a reunion and potential battle between the Leader and the Hulk needs to happen. While several Hulk-related characters have been confirmed to be appearing in Brave New World, Mark Ruffalo himself hasn't been revealed to be returning in Phase 5, meaning he won't yet be reuniting with Sterns. The iconic pair need to meet again in the MCU's future, so the Leader needs to survive Captain America: Brave New World.