Marvel’s upcoming Thunderbolts movie is still shrouded in mystery, but one important piece has fallen into place. The Walking Dead’s Robert Kirkman let slip that actor Steven Yeun is playing The Sentry. This Superman-esque hero is finally making his MCU debut, and that means the entire world should be very, very afraid.
Who is The Sentry, and why is he both the Marvel Universe’s greatest hero and its worst nightmare? Let’s break down the history of this mentally unstable hero and how he may fit into the plot of Thunderbolts. These are the topics we cover here:
- Who Is Steven Yeun’s Thunderbolts Character The Sentry?
- The Sentry’s Powers and Abilities
- The Sentry’s Secret Origin
- The Sentry As an Avenger
- How The Sentry Fits Into the Thunderbolts Movie
Who Is Steven Yeun’s Thunderbolts Character The Sentry?
The Sentry is quite possibly the most powerful superhero in the Marvel Universe. He’s also the most dangerous.
Once an ordinary man named Bob Reynolds, he consumed a serum that granted him “the power of a million exploding suns.” Unfortunately, that power comes at an incredible cost. There’s a dark side to The Sentry’s personality known as The Void. For every act of good The Sentry performs, The Void counteracts it with an evil deed. Fighting against his inner darkness and maintaining his sanity is a losing battle for Bob Reynolds. Still, when the times call for a powerful hero, there’s no one better suited to the job than The Sentry.
The Sentry’s Powers and Abilities
The Sentry’s powers stem from an experimental serum, one of the many formulas developed as a potential replacement for the Super Soldier Serum after World War II. The serum is said to accelerate his molecules an instant forward in time. What that means in practice is that The Sentry is an incredibly strong hero with an almost limitless array of powers.
As The Sentry, Bob’s strength is easily on par with heroes like Hulk and Thor. He can also fly and move at incredible speeds, has enhanced senses and is practically invulnerable. He can also absorb and project energy, allowing him to perform feats like firing energy blasts, teleportation and pacifying a rampaging Hulk. In terms of powers, The Sentry is truly Marvel’s answer to Superman.
As The Void, Bob is arguably even more powerful and dangerous. The Void is a shape-shifting, demonic entity that can do everything from controlling the weather to infesting the minds of others. The Void has easily withstood the combined might of the Avengers, X-Men and Fantastic Four, and even throwing it into the sun has proven to be a temporary solution.
The Sentry’s Secret Origin
The Sentry was created by Paul Jenkins, Rick Veitch and Jae Lee and debuted in the pages of the original The Sentry miniseries in 2000. That series introduces its title character as a forgotten hero from the Marvel Universe’s past. Even Bob Reynolds - a middle-aged, overweight married man - doesn’t remember that he used to be the hero nicknamed “The Golden Guardian of Good.”
Bob regains his memories and becomes The Sentry once more, only to discover his sworn enemy, The Void, has also returned. Over the course of the series, The Sentry’s history with characters like Hulk and the Fantastic Four is established, and The Sentry is retroactively inserted into Marvel continuity.
Ultimately, readers learn that The Sentry and The Void are two halves of the same coin. The world was made to forget about The Sentry in order to protect it from The Void’s wrath. Bob realizes he has no choice but to repeat that act in order to keep his dark side at bay. He once again erases the world’s collective memory of The Sentry, though the series is ambiguous as to whether Bob himself has truly forgotten about his superhuman selves.
The Sentry As an Avenger
The original The Sentry miniseries was a self-contained story, but the character did eventually go on to play a recurring role in the Marvel Universe. The Sentry officially became one of Earth’s Mightiest Heroes in 2004’s New Avengers, joining a radically revamped team alongside characters like Spider-Man, Wolverine and Luke Cage.
New Avengers reintroduces The Sentry as a self-imposed prisoner of The Raft, one who intervenes to stop a massive supervillain jailbreak and reluctantly joins the team in the aftermath. Though a powerful asset to Earth’s Mightiest Heroes, The Sentry fights to preserve his sanity and once again keep The Void at bay.
When the world’s heroes are torn apart by the events of 2006’s Civil War, The Sentry sides with Iron Man’s pro-registration faction. He knows all too well the damage that unchecked power can wreak. The Sentry also proves vital in protecting the world from Hulk’s wrath in 2007’s World War Hulk.
However, The Sentry’s downfall begins in Marve’s 2009 storyline Dark Reign. As Norman Osborn takes control of S.H.I.E.L.D.’s replacement H.A.M.M.E.R., he recruits Bob Reynolds to join his “Dark Avengers.” The Sentry is manipulated into serving alongside villains like Bullseye, Venom and Ares. Osborn gambles that all those years of grappling with his Green Goblin persona will allow him to keep The Sentry under control. That turns out to not be the case.
The Void is finally unleashed in 2010’s Siege, which sees Osborn lead an all-out attack against Asgard. The recently returned Steve Rogers rallies the true Avengers and saves the day, though at the cost of The Sentry’s life.
In the years since, The Sentry has been resurrected and killed again, while new stories have continued to explore the true nature of his powers and the question of whether The Sentry or The Void is the “real” being. Most recently, The Sentry was killed once more in 2020’s King in Black. Marvel’s 2023 The Sentry series explores what happens when the power of The Sentry seeks a new host. Who will become the new Sentry, and will they also have to shoulder the burden that is The Void? Only time will tell.
How The Sentry Fits Into the Thunderbolts Movie
To date, The Sentry hasn’t enjoyed much exposure outside of Marvel’s comics, apart from appearing in a handful of mobile games like Marvel Puzzle Quest, Marvel Future Fight and Marvel Snap. But that will change soon, as Steven Yeun has reportedly been cast as the Golden Guardian of Good in the MCU.
Yeun won’t be starring in a dedicated Sentry movie or series, though (at least, not yet). Instead, he’s debuting in 2025’s Thunderbolts, appearing alongside familiar MCU faces like Sebastian Stan’s Bucky Barnes, Florence Pugh’s Yelena Belova and David Harbour’s Red Guardian.
At this early stage, it’s not clear what exact role The Sentry will play in Thunderbolts. Though, given the character’s comic book history, it’s probably safe to assume the film will play up his status as both a powerful hero and a terrifying villain. Will The Sentry start out as a member of the Thunderbolts, only to become the team’s worst nightmare when he loses control? Given the relative lack of powers on this roster, battling The Sentry would certainly be a monumental task for the Thunderbolts.
We may see Julia Louis-Dreyfus’ Contessa Valentina Allegra de Fontaine play a role similar to that of Norman Osborn in the Dark Avengers comics. Contessa may see Bob Reynolds as a powerful asset to be exploited, only for her control over this dangerously unstable hero to evaporate. If Thunderbolts is basically Marvel’s version of Suicide Squad, then The Sentry may be the film’s Enchantress character.
We also don’t know whether the MCU will touch on the idea that The Sentry is a forgotten hero with deep ties to the rest of the superhero community. Will he be retroactively established as a character who was once very active in the MCU? And just how much will the movie lean on the idea of The Sentry as a twisted analogue of DC’s Superman? We’ll learn more as we move closer to the July 2025 release date of Thunderbolts.
For more on the future of the MCU, read our full breakdown of the ending to The Marvels and see all the Marvel movies and shows in development.
Jesse is a mild-mannered staff writer for IGN. Allow him to lend a machete to your intellectual thicket by following @jschedeen on Twitter.
