Who is Bob in ‘Thunderbolts*?’ The MCU’s most powerful hero yet, explained

The big appeal of Marvel’s Thunderbolts* is that it brings together a bunch of anti-heroes and villains from the MCU’s past for their very own team-up movie. A little bit like DC’s Suicide Squad. Task Force Xerox, you might say.

Having said that, director Jake Schreier’s movie will introduce one major new addition into Marvel lore at the same time ⏤ and honestly, if the studio handles this character right, the MCU might never be the same again. That’s how powerful this guy is. The name of this heavy-hitter who could take on Superman in a slugging match? Bob.

Easily the movie’s biggest secret (outside of what that pesky asterisk actually means), Thunderbolts* promises not to reveal too much about Lewis Pullman’s Bob before the movie comes out. But, actually, we don’t need to wait that long to find out the answers. Don’t be fooled by his commonplace name ⏤ Bob is a big deal. Here’s why.

Who is Bob and what is his connection to Sentry?

In what is the worst-kept Marvel secret since Joe Locke as (probably) Wiccan in Agatha All Along, the real identity of Bob is also already known. Bob can only be Bob Reynolds, aka the Sentry. We even get a glimpse at the Sentry insignia in the first Thunderbolts* trailer!

Way back in February 2023, Invincible star Steven Yeun was originally due to play Bob/Sentry in the project, even though Marvel was trying to keep this fact under wraps. However, in January 2024, the Oscar-winning star was forced to exit the production due to scheduling conflicts stirred up by the strikes delaying filming from last summer to this spring.

Mere weeks later, though, a new Sentry rose up in the form of Lewis Pullman, perhaps best known for his role in Top Gun: Maverick. Fans immediately took Pullman into their hearts and welcomed him into the MCU family, and there’s a strong hope that he’s the perfect person to bring the MCU’s new most powerful hero to life.

But, wait ⏤ is the Sentry really Marvel’s number-one strongest hero, beating out the likes of Thor and Captain Marvel (played by Pullman’s Lessons in Chemistry co-star Brie Larson)? And, if so, how?

What is the Sentry’s origin story?

In the comics, Robert (not Ryan) Reynolds is an omega-level threat who’s gone up against the likes of Doctor Doom and held his own, but historically he hasn’t been given much respect. Perhaps his incoming MCU debut could finally turn things around for the Golden Guardian of Good.

Although he was only created in 2000, by Paul Jenkins, Jae Lee, and Rick Veitch, Sentry is canonically one of the earliest superheroes in Marvel comics, preceding even the Fantastic Four. Most view him as simply an obvious analogue for DC’s Superman, but he’s still a valiant hero in his own right with a fascinating history.

In 1947, Canada’s Department K and the United States’ Operation: Rebirth merged to form Project Sentry. The intent behind this union was to take the super soldier serum that was used to make Steve Rogers’ Captain America to the next level, but the Cold War fragmented the operation and multiple sub-projects emerged. As a result, it was hard to keep track of all the data and resources throughout the years and Project Sentry’s lab work found its way to an unnamed professor who experimented with the formula and perfected it.

Robert was a troublemaker as a teenager and addicted to meth. He snuck into the professor’s lab and consumed the Golden Sentry Serum, which gave him the power of a million exploding suns. It created an explosion and he grew in strength, but it incidentally killed his partner and the security guards. Robert asked the professor to create more of the serum and later Project Sentry wanted to run tests on him, but he ultimately chose instead to go out into the world and become the superhero Sentry after getting into a fight with school bullies.

Sentry #1 presents Robert Reynolds in the modern age as a middle-aged man who has forgotten that he was a superhero. He has flashbacks of his historic adventures as a superhero who fought alongside other heroes to defeat the Void, a dark entity that embodies negativity. The Void tells Robert that he’s coming back, and this pushes Robert into a state of madness that pushes his wife away from him and he becomes the Sentry again. When he does, the Void changes the story and tells him he’s not a hero, leading Robert to question what’s real and what’s not.

To make matters more confusing, the other heroes don’t remember the Sentry, including Reed Richards/Mr. Fantastic, but when Robert says the word “unicorn” during their conversation, something clicks. It leads Reed to investigate a unicorn statue that was given to him for being Robert’s best man at his wedding. It was real after all, and Robert fully accepts his superhero identity and prepares to battle the Void.

How is the Sentry connected to the Thunderbolts?

Valentina Allegra De Fontaine (Julia Louis-Dreyfus) has been assembling a team of anti-heroes from across the MCU for the purpose of putting together a team that can get things done that the Avengers can’t. In Black Panther: Wakanda Forever, powerful nations intend to attain the country’s Vibranium. Valentina is the director of the CIA and the U.S. government steals MIT student Riri Williams’ vibration-finding radar, leading many to believe that she (and therefore the Thunderbolts) will want to complete this mission. The question is, how does Sentry fit into all of this?

Sentry was born from a top-secret program and as Valentina’s actions confirm, there are governmental parties working in the shadows to address this superhero situation. Project Sentry could be something she’s aware of for the purpose of the United States having its own superpowered hero on call. Valentina is the type of character who has plans on top of plans, and no one should underestimate the lengths she’d go to complete an objective.

If Marvel Studios decides to remain more faithful to the comics, it would make sense for Sentry to have his own solo project after Thunderbolts. Robert Reynolds’ story is complex and deeply personal, and it would need time to explore the heavier themes, especially if it includes Sentry: Reborn by Jenkins and John Romita Jr., where Robert is diagnosed with schizophrenia. It would be essential to also nail down how Sentry stands on his own, and that he’s not just a Superman clone.

The Sentry might be the toughest page-to-screen adaptation the MCU’s ever had to tackle, but the rewards could be well worth it.