Who Is Sentry? The MCU’s Version Of Superman Explained

Steven Yeun’s MCU role seems to have been confirmed to be the Sentry, marking the live-action debut of the Marvel Comics hero in Marvel Studios’ upcoming Thunderbolts. Steven Yeun, star of The Walking Dead, Minari, Invincible, and Beef, joined the cast of the MCU’s Thunderbolts project in February 2023 in an undisclosed role. Following news of his casting, theories began to emerge positing which Marvel Comics character Steven Yeun may be bringing to life in Thunderbolts, with some noting that Yeun could portray Amadeus Cho, a.k.a. Hulk-related Brawn, or even rumored Fantastic Four villain Doctor Doom, yet one even more popular casting theory now appears to have been accidentally confirmed.

Steven Yeun joining the cast of Marvel Studios’ Thunderbolts was exciting news, particularly since Yeun’s career has gained more traction in recent years. Following a six-year run on The Walking Dead, in which Yeun portrayed Glenn Rhee, Yeun began to see more high-profile success with feature films including Okja, Sorry to Bother You, Nope, and Minari, with the latter earning him an Academy Award nomination for Best Actor, making him the first Asian American actor to do so. More recently, Yeun portrayed Danny in Beef on Netflix, and voiced the titular hero Mark Grayson in Invincible, and it seems he’ll soon be donning a superhero suit in live-action for Thunderbolts.

Steven Yeun Is Playing Sentry In Thunderbolts

Since the announcement of Steven Yeun’s casting, the most popular casting theory hinted at him portraying the MCU’s version of Marvel Comics’ Robert Reynolds, a.k.a. the Sentry. While there has been no official confirmation from Marvel Studios, The Walking Dead and Invincible creator Robert Kirkman may have inadvertently substantiated the rumor. Speaking to David Finch (via YouTube), Kirkman revealed that Yeun had called him following a costume fitting for the Sentry, with the pair joking that Yeun has a habit of portraying yellow-and-blue-suited superheroes. This all but confirms that Steven Yeun will in fact be portraying the MCU’s Sentry, raising excitement for his role in Marvel Studios’ Thunderbolts.

It’s unclear what role the Sentry will have in Thunderbolts, though speculation suggests that he could initially be depicted as the villain to the Thunderbolts team. In Marvel Comics, Sentry is a staunch superhero with a dark side, so perhaps this darkness could be put on display in his MCU debut, allowing him to face the team comprised of Bucky Barnes, Yelena Belova, Red Guardian, Taskmaster, US Agent, Ghost, and Contessa Valentina Allegra de Fontaine. While he may initially be depicted as a villain, it’s possible that Steven Yeun could have a bright future ahead of him in the MCU, as Sentry is one of Marvel Comics’ most powerful characters.

Sentry’s Marvel Comics Origin

Robert Reynolds debuted in Marvel Comics’ Sentry #1 in 2000, introduced as a middle-aged and overweight Everyman character who wakes up one day remembering that he used to be the Sentry, a superhero with the “power of one million exploding suns.” Reynolds’ first story sees him approaching high-profile heroes of the Marvel Universe in an attempt to also get them to remember him, including the likes of Mister Fantastic, the Hulk, Spider-Man, and Doctor Strange. It was later revealed that a meth-addicted Reynolds became the Sentry after inadvertently consuming an experimental super-soldier serum in an effort to fuel his addiction, and this darkness permeated through his career as a superhero.

While remembering that he is the Sentry, Robert Reynolds also remembers his archenemy, the Void. However, Reynolds and Reed Richards soon learn that the Sentry and the Void are two sides to the same person, which once forced the Sentry and the heroes of Earth to wipe the world’s memory of the Sentry to spare them from the Void. Eventually, Reynolds joins the Avengers as the Sentry, but his psychological problems worsen as he constantly fails to reconcile his Robert Reynolds, Sentry, and Void personas. This leads to some dark but powerful storylines for the Sentry, which would be great to see adapted into the live-action MCU.

How Powerful Is Sentry?

In Marvel Comics, the Sentry’s powers are derived from an experimental super-soldier serum that moves his molecules an instant ahead of the current timeline, granting him some incredible gifts that are supposedly a thousand times stronger than those of the original Captain America. Due to this fact, the exact limits of the Sentry’s abilities are not known, though he has been shown to be able to lift a helicarrier, hold off a Celestial, fight Thor hand-to-hand, and dispatch of Carnage, Ultron, and Terrax the Tamer, a herald of the planet-eater Galactus. However, the Sentry’s strength isn’t the only ability he possesses.

The Sentry also has superhuman speed and enhanced senses, has the ability to fly, and is practically invulnerable, with SHIELD Director Nick Fury noting they know of no ways to kill him, and Iron Man’s scanners picking up no weaknesses in his body. The Sentry can absorb and project huge amounts of energy, has displayed the ability to teleport himself in an instant, and is a remarkably powerful telepath. His simultaneous existence in the past, present, and future has lead some to speculate that time may simply bend itself around the Sentry, meaning that situations usually work in his favor, as he can manipulate time and probability to his will.

Although the Sentry is one of Marvel Comics’ most formidable superheroes, his evil alter ego, the Void, is also incredibly powerful, which means he poses one of the greatest threats to the Marvel Universe. It’s claimed that for every benevolent act the Sentry performs, the Void retorts with an act of malevolence. The Void is usually depicted in a demonic form, capable of battling Thor and killing Loki with ease. The Void has the ability to shape-shift, and can control the weather to create destructive storms, and the Void is at its most powerful in the Negative Zone, a popular location for the Fantastic Four and other Marvel heroes.

Why Sentry Is Marvel’s Answer To Superman

The Sentry is often referred to as Marvel Comics’ answer to DC Comics’ Superman, the legendary caped Kryptonian who operates on Earth as a protective hero. Both Superman and the Sentry share many similar abilities, including enhanced strength, senses, flight, speed, and invulnerability, yet Robert Reynolds’ Void persona sets him apart from the DC hero. While there are certainly similarities between the Sentry and Superman, there are more than enough differences to allow Steven Yeun’s debut as the Sentry in Thunderbolts to feel fresh and exciting. Although Marvel Studios hasn’t yet provided an official confirmation of Yeun’s Sentry casting, his appearance in Thunderbolts will nonetheless be a spectacle.