This article tells a story—a story about a superhero that nobody really remembers. Most importantly, this superhero is soon going to make his debut in the Marvel Cinematic Universe (MCU), and he will likely play a significant role, provided his introduction is handled well.
This story is about Sentry. In the upcoming “Thunderbolts,” we will see an epic and complex character like Sentry. While everyone may have heard the name, not many people know much about him, much like his comic book origins. Therefore, this article will provide the complete comic book origin of this superhero, woven into a narrative.
Sentry’s Origins
Sentry first appeared in the year 2000 in the miniseries The Sentry, created by Paul Jenkins, with the intention of introducing a new character deeply connected to Marvel’s history.
The story of Sentry begins with Robert Reynolds, or Bob, who wakes up one night feeling restless. His wife tells him to go back to sleep, but unable to, he decides to take his dog for a walk. However, Bob’s restlessness stems from something deeper: he has started to feel the presence of a dark entity.
Bob was an ordinary man living a seemingly normal life, with everything going well. However, one day, he finds a book on his shelf. Upon opening it, he sees a bottle inside and is reminded of his alcohol habit. Yet Bob’s mind is consumed by something else entirely—he begins to feel that he is, in fact, a superhero.
He starts to realize that he is Sentry, a superhero who has existed for many years. His powers came from a much more dangerous version of the Super Soldier Serum that empowered Captain America.
After the success of the Super Soldier Serum and the creation of Captain America, many governments around the world tried to create a similar serum, seeking to improve upon it further. In this race to develop a better Super Soldier Serum, the governments of Canada and the United States jointly launched Project Sentry in 1947. This project wasn’t just about creating a serum; they aimed to make it a hundred thousand times more powerful. However, after many failed attempts, the government eventually handed the project over to private companies for further research and development. Over the next 30 years, Project Sentry was divided into thousands of sub-projects, with its details spread across several private companies worldwide. This fragmentation is one reason we see so many super soldiers in Marvel. Over time, the government forgot about this project.
Sentry’s Discovery of His Powers
A few years later, a boy named Robert “Bob” Reynolds, who was a drug addict, randomly broke into a laboratory, hoping to find some drugs. Instead, he found the Golden Sentry Serum, which a professor had been developing for many years. Without thinking, Robert drank the entire serum, and within minutes, he gained the power of a million exploding suns. This serum was thousands of times more powerful than Captain America’s serum, giving Robert superpowers that no superhero of that time possessed.
Because of this immense power, Sentry was incredibly strong. He became the first superhero in Marvel Comics, teaming up with various superheroes like the Fantastic Four, the Avengers, Hulk, Spider-Man, and many others. He defeated many powerful villains and saved Earth multiple times, yet no one remembers him.
The Rise of Void
As Bob continued reflecting on these revelations, his mind increasingly focused on the dark entity known as the Void. Just as he was processing these thoughts, he suddenly heard a voice behind him. He turned around to see that the Void had possessed his dog. Bob struck the dog, and while the Void fled, his dog was injured.
Hearing the noise, Bob’s wife arrived and accused him of drinking again. They argued, and she told him she couldn’t live with him anymore, leaving him. But Bob’s mind was elsewhere. He opened his wardrobe and found a jacket that appeared quite ordinary, except for a cape hanging at the back, clipped to a hanger with clothespins. After putting it on, he declared, “I’ve found my Sentry suit.”
Anyone else would think Bob had lost his mind, but then something extraordinary happened. Bob stepped out of his house and began to fly, confirming that he possessed some kind of power. But what exactly were these powers, where did they come from, and why didn’t anyone remember him?
Forgotten by the World
To find answers, Bob went to Reed Richards. Normally, Reed wouldn’t entertain such claims, but since Bob had managed to sit atop Reed’s building—penetrating a force field that no normal human or superhero could breach—Reed was intrigued.
Bob approached Reed and asked, “Do you remember me? Do you know who Sentry is?” Reed responded that he had no idea what Bob was talking about. Bob explained that they were once best friends, to which Reed retorted, “Have you had too much to drink tonight?” Bob then realized that, like the rest of the world, even Reed Richards didn’t remember him. Bob pressed on, asking, “Do you remember attending a wedding that had a unicorn?”
Hearing this, Reed remained confused, and Bob left. Reed later went down to the rest of the Fantastic Four and asked Susan, “Did we ever attend a wedding with a unicorn?” Susan didn’t recall anything, but the moment the word “unicorn” was mentioned, a golden unicorn suddenly appeared. This meant that the unicorn had always existed, but since no one remembered Sentry, no one had been able to perceive it. Along with the unicorn, there was a videotape. Reed picks it up and plays it, and they are all shocked to see a message from Reed himself.
In the message, Reed tells his team that if they are watching the footage, it means a man named Bob or Robert Reynolds, who is talking about Sentry, has visited them, and under no circumstances should they try to remember who Sentry is. Reed, in particular, must not dig deeper into the matter because if Sentry has returned, it means that Void has also returned. But before Reed can process any more, the footage cuts off, leaving Reed with many questions.
Meanwhile, Bob meets Hulk and greets him by saying, “Hey, Bruce.” If you know anything about Hulk, he doesn’t like to be called Bruce. At this point, we expect Hulk not to recognize Bob, and that a fight will break out. Hulk does jump at him, but in happiness, because Hulk actually remembers who Bob is. Hulk explains that he remembers Bob because Bob is a part of Hulk’s personality. Most likely, Bruce Banner himself has no memory of Bob, but because Hulk and Bruce are separate personalities, Hulk still remembers that Bob is Sentry and that they used to be good friends.
During this whole sequence, we can see that the clothespins that were holding Sentry’s cape are slowly transforming into his full suit. Bob tells Hulk that Void is also coming back, which scares Hulk. Imagine how terrifying Void must be for Hulk to be afraid just by hearing his name. But Bob tells him not to worry and conjures a miniature sun, handing it to Hulk, so he can use it when needed.
On the other hand, Reed Richards continues to struggle, trying to figure out who Robert Reynolds and Sentry really are. He finds some clues in his basement, but before he can get too far, Doctor Strange appears and warns him that he doesn’t need to do what he’s doing. Doctor Strange remembers exactly who Sentry is. He shows Reed a magical video clip between his fingers, where Reed and the Fantastic Four are shown creating a machine. In the message, a future version of Reed tells Doctor Strange that if he ever tries to remember who Sentry is, Strange must stop him.
Doctor Strange explains that Reed doesn’t need to investigate further, and he tears up the documents Reed had found before leaving. Meanwhile, Bob meets Spider-Man, who had once taken Sentry’s photo. But now, Spider-Man remembers nothing about him. Sentry calls him Peter and shows him a picture that Peter had taken of him. But because Peter doesn’t remember Sentry, the picture appears as a blank piece of paper to him, and he leaves.
Bob tells Peter to figure out why some magazine issues are missing. Peter doesn’t pay attention at the time but later starts researching it at the Daily Bugle. He discovers that some magazine issues are indeed missing, and it finally clicks that Sentry did exist. All of Peter’s memories of Sentry start coming back. After that, Bob goes to see Professor Xavier, the most powerful telepath. He tries to communicate with Xavier, but even Xavier doesn’t remember anything. Before leaving, Bob tells him, “The Void is coming,” which strangely frightens Xavier.
As more and more people begin recalling their memories, Bob, now Sentry, finds a giant watchtower in the middle of the city, which was actually his home. The watchtower had always existed in New York City, but since no one had any memory of Sentry or events related to him, no one could perceive it. But as soon as Bob remembers who he is, the tower becomes visible to him. He goes inside and finds a computer that immediately recognizes him as Bob. Bob starts asking it questions, and the computer answers them correctly.
When Bob asks why no one remembers him, the computer reveals that it has a virus preventing it from sharing further information or reminding people who Sentry is. Bob digs deeper and discovers that the virus is actually a transmitter powered by his own serum. Bob asks who installed and activated the transmitter, and the computer replies, “Sentry did it himself.” This revelation shocks Bob, as he realizes that he had been erasing his own memories from others’ minds.
You can think of this situation as similar to “Spider-Man: No Way Home,” where Peter Parker asks Doctor Strange to cast a spell that makes everyone forget who he is. In this case, though, it’s not magic but science. Bob destroys the transmitter, releasing a shockwave that restores everyone’s memories of Sentry. Posters of Sentry reappear on the walls, old action figures that people had bought in the past become visible again, and everyone remembers just how great a superhero Sentry was. And with that, Void arrives. Sentry asks Void, “What do you want?” Void replies, “The end of the world, and after that, I will move on to another world. And I’m never going to stop.”
Hearing this, Sentry flies into the sky and informs the whole world that he’s back, but this also means Void is back too. He assures everyone not to worry, as he will save them, but he will need the help of other superheroes for this fight. The fight is set to take place in front of the Statue of Liberty. Sentry reaches the Statue of Liberty, and other superheroes and supervillains arrive because they all know how dangerous Void is.
The Shocking Revelation of Void
At this moment, Reed Richards also arrives. Sentry knows what Reed had done—he had created the device that made the whole world forget who Sentry was, and because of that, Sentry is angry at Reed. Reed tries to explain, but before they can resolve things, Void shows up, and the fighting begins. Hulk tries to attack Void but is thrown aside. Hulk is so terrified that he uses the miniature sun that Sentry gave him to protect himself. No other superhero can stand up to Void.
Amid the battle, Doctor Strange approaches Reed and tells him that enough is enough, and that he needs to show him something. He restores Reed’s final memory, where he and his team had placed the transmitter in the watchtower. And the one who activated it was none other than Sentry himself. The reason for this shocks Reed—when Void had attacked New York the last time, he was extremely dangerous. He even broke a bridge in half.
As they dig deeper, they realize that Void is actually Sentry himself. There’s no need for confusion; you can understand it as Robert Reynolds having Dissociative Identity Disorder (similar to Moon Knight). Multiple personalities exist within his body, and because he possesses so much power, his different personalities use that power in various ways. This is why Sentry is so different from Robert Reynolds, and Void is so different from Sentry.
They somehow manage to calm Sentry down, and Void vanishes along with him. The team reminds Sentry of his true nature, and he finally remembers that Void and Sentry are both him. After realizing the truth, with no other option left, Sentry once again installs the transmitter in the watchtower, deciding that it’s better for the world to forget who Sentry is because if they forget Sentry, they’ll also forget Void.
Sentry’s Return
But as the comic ends, we realize that Robert Reynolds hasn’t completely forgotten that he is Sentry. He goes to a food joint where his sidekick works, and when his sidekick asks him what he wants to eat, old memories flash in Bob’s mind, and he smiles. This actually shows that perhaps Bob Reynolds hasn’t forgotten that he is Sentry.
Later, in the “New Avengers,” his memories fully return when Emma Frost enters his mind, as they all need Sentry. She unlocks his memories, and Bob Reynolds once again remembers who he is. He doesn’t like it; he doesn’t want to be Sentry because he knows that with Sentry comes Void. But Marvel Comics needed a new superhero, so they revived Sentry.
You should know that Sentry is a very powerful superhero. Just to give you an idea of his achievements: remember the “World War Hulk” story, where stopping Hulk was impossible? Worldbreaker Hulk was the most dangerous version at the time, so they called in Sentry. Sentry and Hulk fought each other, and they beat each other down so hard that they reverted to their human forms.
As for Silver Surfer, just like him, Galactus has several heralds. One of them, Terrax, tried to attack Sentry with his axe, but Sentry stopped him just by grabbing his hand. No matter how much strength Terrax applied, he couldn’t budge. Sentry has fought Thor countless times, and every time, he’s beaten Thor. Once, when Thor threw Mjolnir at him, Sentry, who had the Death Seed at that time, used his telekinesis to stop the hammer in mid-air.
Sentry has also torn Ares, the God of War, in half, and finished off Carnage. In fact, he is one of the main reasons behind “Secret Wars.” Molecule Man, a superhero who can alter the molecules of anything, came face to face with Sentry, but Sentry manipulated Molecule Man’s matter and exploded him. And because Sentry has similar powers, he can also manipulate matter and molecules.
Small things like helicopters and aircraft mean nothing to Sentry—he operates on a cosmic level. He wasn’t made for Earth; he was made for space. He comes and goes whenever he pleases, and no one, not even his wife, knows where he goes.
In one storyline, Sentry wipes out all the superheroes and the world, including Doctor Doom. No one could stop him. From this, you can understand just how dangerous Sentry is. I’m pretty sure that in the MCU, they won’t show him at this level. They will likely nerf him a lot, but I hope they don’t do it too much.
