10 Best MCU Villains We Never Saw Coming, Ranked

For every great hero, there must be a devious villain to challenge them, and the Marvel Cinematic Universe (MCU) is packed with some truly memorable supervillains to keep Marvel's mightiest superheroes on their toes. While many of the MCU's most prominent villains can be identified from a mile away, some of the most effective enemies conceal either their true intentions or identity until a shocking reveal. From old friends manipulated and broken by insidious forces to supposed mentors possessing secretly sinister agendas, these stunning displays of deception leave fans gasping in shock.

Here are the 10 biggest and most surprising betrayals and true villain reveals in the MCU, all of which have rocked Earth's Mightiest Heroes — and the audience — to their core. And with even some of the most trusted heroes in the MCU breaking bad, these shocking turns continue to leave fans talking years after the fact.

"Captain America: The Winter Soldier" begins with Captain America (Chris Evans) working under Nick Fury (Samuel L. Jackson) for SHIELD. Fury himself operates directly alongside Alexander Pierce (Robert Redford), a SHIELD official and member of the World Security Council. Fury explains that Pierce personally recruited him to work for SHIELD after a daring mission in Bogotá. The level of trust between the two men at the beginning of "The Winter Soldier" is evident as they prepare to launch the ambitious Project Insight to better protect the country. This makes it all the more heartbreaking when Pierce is revealed to be a member of the clandestine terrorist organization HYDRA and arranges for Fury's assassination.

"The Winter Soldier" sent a shockwave through the MCU with the revelation that HYDRA had remained active since World War II, secretly steering the course of history and quietly infiltrating SHIELD on virtually every level. While some double agents working for HYDRA are more obvious, including the gruff combat specialist Brock Rumlow (Frank Grillo), Pierce is a bigger surprise given how much Fury initially trusts him. Pierce shows his true allegiance when he privately meets with the Winter Soldier (Sebastian Stan) at his home, going as far as to murder his housekeeper to maintain his secret. Pierce's murderous betrayal leads Fury to remark that this is why he has trust issues.

The 2019 film "Captain Marvel" focuses on the cosmic war between the Skrulls and Kree as Carol Danvers (Brie Larson) learns the truth about her past and embraces her superhero destiny. Leading the Kree Empire is an advanced artificial intelligence known as the Supreme Intelligence, who appears to Carol in the form of her Air Force mentor Wendy Lawson (Annette Bening). The Supreme Intelligence offers Carol words of wisdom in mastering her powers and guidance as she travels the stellar expanse on behalf of the Kree. But this all proves to be an elaborate ruse, with the Supreme Intelligence quietly manipulating Carol for her connection to the Tesseract and Infinity Stone within it while positioning the Skrulls as antagonistic figures rather than oppressed refugees.

"Captain Marvel" sets up Carol to be betrayed by both of her mentor figures within the Kree — the Supreme Intelligence and her unit commander Yon-Rogg (Jude Law) of the Kree Empire's Starforce. While Yon-Rogg's eventual turn is clearly telegraphed earlier in the film, the Supreme Intelligence's appearance as Lawson and Lawson's Kree alter ego Mar-Vell helps conceal their deception. Revealing their true nature after the Kree spring their trap, the Supreme Intelligence's sinister turn puts Captain Marvel on the defensive like never before. It is following this manipulation that Carol defiantly unleashes the full extent of her powers; she just needed the Supreme Intelligence's villainous push to provide a little unintended motivation.

The Disney+ series "Hawkeye" features the return of Clint Barton (Jeremy Renner) after the events of "Avengers: Endgame" just in time to help mentor another superhero archer, Kate Bishop (Hailee Steinfeld). As Kate and Clint take on a criminal gang known as the Tracksuit Mafia during the holiday season in Manhattan, they contend with Kate's discerning mother Eleanor (Vera Farmiga), who disapproves of her daughter's rebellious nature. Kate quickly becomes suspicious of her mother's boyfriend Jack Duquesne (Tony Dalton), who appears to have a criminal background. The murder of Duquesne's uncle Armand (Simon Callow) only heightens her concerns. However, Kate and Clint eventually discover that Duquesne was framed for this crime by none other than Eleanor, the true culprit and Armand's murderer from the jump.

During her adventure with Clint, Kate meets and befriends Yelena Belova (Florence Pugh), who has been summoned to New York City to assassinate Clint by a mysterious benefactor. Yelena reveals to Kate that she was hired by Eleanor, who is secretly in league with the Kingpin (Vincent D'Onofrio), framing Duquesne to deflect any suspicion away from her criminal activities. This heel turn is effectively masked by Dalton's performance as Duquesne, whose character has a slightly more antagonistic history in the comic book source material. While the Kingpin's return to the MCU may have overshadowed Eleanor's villainous nature, the reveal is a genuine surprise and crucial in helping inform Kate's fledgling superhero journey.

Of all the horrors of war that Steve Rogers has witnessed firsthand, none haunt him more than the loss of his lifelong friend Bucky Barnes during World War II. Believing Bucky to be killed in action during a mission against HYDRA, Steve continues to ruminate on Bucky's apparent demise after regaining consciousness in the 21st century. While working for SHIELD, Steve learns of the existence of a legendary masked assassin known simply as the Winter Soldier who has been active since the Cold War. When Steve finally manages to unmask the lethal HYDRA operative, the tragedy of Bucky Barnes is only exacerbated as the two old friends stand reunited, albeit on opposing sides of a fiery conflict.

In Bucky's defense, his villainous path is foisted upon him when the evil Arnim Zola (Toby Jones) has HYDRA recover his body and subject Bucky to extreme brainwashing in order to turn him into the ultimate killing machine. The utterance of a handful of trigger words can snap Bucky instantly into the emotionless and dangerous Winter Soldier, making even someone like Steve a doomed target. Steve emerges from his cryogenic slumber believing his best friend to have died decades ago, only to discover Bucky has similarly survived the passage of time. Bucky eventually redeems himself and overcomes his mental programming, but only after menacing the MCU as one of the deadliest assassins it has ever known.

The 2021 film "Eternals" unveils a hidden history of the MCU. The eponymous ensemble live among humanity for millennia as they hunt the monstrous Deviants on behalf of their creators, the Celestials. Among the most prominent of the Eternals is Ikaris (Richard Madden), a classic superhero paradigm with a wide array of powers who is held in high regard by most of his Eternal contemporaries. The Eternals reassemble centuries after parting ways in the wake of a new Deviant sighting, along with the death of their leader Ajak (Salma Hayek). The Eternals decide to defy the Celestials by preventing the planet-destroying emergence of a new Celestial on Earth, however this plan is violently opposed by Ikaris.

Ikaris reveals he knew of the Celestials' true plans for Earth for centuries and personally had Ajak killed when she attempted to stop the emergence herself. Prepared to kill the rest of the Eternals to ensure the Celestials succeed, Ikaris fiercely battles his friends in order to carry out his mission at any cost. While "Eternals" positions the sullen Druig (Barry Keoghan) as a possible traitor in the group, complete with suspicious mind control powers, this all proves to be an elaborate misdirect from Ikaris' heel turn. Ikaris is an unquestionably faithful pawn in the Celestials' grand scheme and this unwavering loyalty leads him to turn on his cosmic family with lethal force.

No king stands alone and among the closest and most trusted figures in the life of T'Challa (Chadwick Boseman) is W'Kabi (Daniel Kaluuya), the Wakandan regent's best friend and confidant. The head of the Border Tribe, W'Kabi is personally responsible for keeping Wakanda safe and remains haunted by the murder of his father by the arms dealer Ulysses Klaue (Andy Serkis) years prior to "Black Panther." This leads to a deep rift between W'Kabi and T'Challa when the Black Panther fails to bring Klaue to face Wakandan justice despite T'Challa promising to do so. And in the wake of this failure, W'Kabi decides to side with T'Challa's secret cousin Erik "Killmonger" Stevens (Michael B. Jordan) in his challenge to the Wakandan throne.

Killmonger instantly earns W'Kabi's support when he murders Klaue and brings the body to the Border Tribe to gain entry into Wakanda. W'Kabi continues to stand behind Killmonger when the latter plots to use Wakandan technology to attack the outside world, leading the Border Tribe against his beloved Okoye (Danai Gurira). What results is an ugly internal conflict when W'Kabi refuses to defuse the situation by telling the Border Tribe stand down, leading to his eventual defeat and imprisonment by Okoye. In his obsession to see his father avenged, W'Kabi turns his back on Wakanda and those in his life that he held dear, and this betrayal ultimately cost him everything.

The great-niece of Peggy Carter (Hayley Atwell), Sharon Carter (Emily VanCamp) decides to follow in her great-aunt's footsteps and becomes an accomplished SHIELD operative and secret agent in her own right. Just as Sharon is poised to bring her relationship with Captain America to the next level, she's labeled a traitor to the American government for siding with Steve Rogers' faction during "Captain America: Civil War." While Rogers leads his allies on the run around the world, Sharon hides out in the Southeast Asian island nation of Madripoor, forced to completely rebuild her life. This abrupt and drastic change in her status quo hardens Sharon, which becomes evident when she reunites with Sam Wilson (Anthony Mackie) and Bucky in the miniseries "The Falcon and the Winter Soldier."

Sam and Bucky learn that Madripoor is run by a shadowy figure known as the Power Broker, whose influence spreads to illicit corners around the world. In the series finale, Sharon is revealed to have been the Power Broker all along, murdering Batroc (Georges St-Pierre) and Karli Morgenthau (Erin Kellyman) to maintain her secret. With the world unaware of Sharon's double life, her name is cleared, and she is welcomed to serve within the CIA while secretly planning to use this new position to sell confidential information. Though she was unceremoniously abandoned by Captain America, Sharon's new direction may leave the Avengers wishing they took better care of her as she becomes a deadly force to be reckoned with.

Taking advantage of the chaotic aftermath of "Avengers: Endgame," Quentin Beck (Jake Gyllenhaal), better known under his masked moniker as Mysterio, presents himself as a superhero from another universe. Mysterio claims repeated use of the Infinity Gauntlet weakened the barriers of the multiverse, causing elemental forces to wreak havoc around the globe, with Mysterio approaching SHIELD to lend his support. This partnership eventually pairs Mysterio with Spider-Man (Tom Holland) in "Spider-Man: Far from Home," with the two heroes working together to stop the elemental enemies across Europe. Feeling that Mysterio is the more competent out of the two of them, Spider-Man entrusts him with an experimental set of glasses that can control Stark Industries' orbital weapons system.

Mysterio's presumed superhero reputation is all an elaborate ruse by Mysterio and a group of disgruntled ex-Stark Industries employees, each of whom holds a deep grudge against Tony Stark (Robert Downey, Jr.) and his legacy. Now armed with Stark's devastating automated weapons system, Beck plots to position himself as the world's greatest hero, no matter how much collateral damage he unleashes to further the deception. Given his villainous legacy, comic book fans may have been naturally wary of Mysterio from the get-go, but his supposedly multiversal origins and rapport with Peter helps deflect suspicion. Mysterio provides Spider-Man with his first major challenge outside of Iron Man's shadow and by the time the dust settles, Mysterio's betrayal upends Peter's life forever.

In the aftermath of "Avengers: Endgame," Wanda Maximoff (Elizabeth Olsen) finds herself living out sitcom-inspired domestic fantasies in the nondescript New Jersey suburb of Westview in the miniseries "WandaVision." As Wanda is somehow happily reunited with the formerly deceased Vision (Paul Bettany) and begins raising a family with him, she's frequently visited by her nosy neighbor Agnes (Kathryn Hahn). However, this fabricated domestic bliss is interrupted when Agnes reveals her true identity is Agatha Harkness, a witch who has survived since the 17th century and targets Wanda for her unique mastery over chaos magic. In addition to constantly intruding on Wanda and her family, Agatha is behind all of her neighbors' recent misfortune since moving into Westview, including the death of beloved family dog Sparky.

Agatha's big reveal at the end of the seventh episode of "WandaVision" sets the show completely on its head as the evil witch gleefully breaks the fourth wall to take credit for all of her dastardly deeds. The sequence is backed with its own catchy theme song, which won a Grammy Award and inspired its own line of merchandise. Agatha confronting Wanda gives "WandaVision" a real sense of stakes and peril, with Hahn's acclaimed performance helping Agatha land her own spinoff series potentially titled "Agatha: Coven of Choas." And more than just make the walls of reality collapse around Wanda in a magical duel, Agatha's heel turn helps push one fan-favorite Avenger into transforming into a supervillain themselves.

Is there any hero in the MCU with a more heartbreakingly tragic trajectory than the Scarlet Witch? From losing her family to an errant weapon produced by Stark Industries to HYDRA and Ultron using her as a pawn, all the way up to Agatha pulling her puppet strings in "WandaVision," the crimson-clad Avenger has an extensive history of manipulation at the hands of powerful forces. She finally snaps in "Doctor Strange in the Multiverse of Madness," and sets out to obtain her happy ending at any cost. Corrupted by the black magic by drawing power from the Darkhold, Wanda hunts the multiversal hero America Chavez (Xochitl Gomez) to gain her powers and find a reality where she can be reunited with her children, viciously dispatching anyone who stands in her way.

"The Multiverse of Madness" wisely kept Wanda's heel turn from virtually all of the marketing leading up to the film's release. When Wanda unleashes her full fury as the Scarlet Witch on Doctor Strange (Benedict Cumberbatch), she does so with some of the most brutal violence seen in the MCU to date. Wanda Maximoff was once heralded among the most powerful of Earth's Mightiest Heroes, nearly able to singlehandedly take down Thanos (Josh Brolin) in "Endgame." Having lost everything and corrupted by forces outside of her control, Wanda becomes one of the MCU's biggest betrayals and perhaps the scariest supervillain it has ever known.