The concept of a “Secret Invasion” was seeded by writer Brian Michael Bendis for years before the main event comic was published. The central idea grew out of the fallout from earlier storylines like `avengers_disassembled` and `house_of_m`, which had fractured the superhero community. The first major, overt clue was the reveal of Elektra as a Skrull in New Avengers #31 (August 2007). This shocking moment served as the starting pistol for the slow-burn reveal of the Skrull infiltration. The core limited series, titled Secret Invasion, was an eight-issue miniseries written by Bendis with art by Leinil Francis Yu. It ran from June 2008 to January 2009. The event was a massive publishing initiative for Marvel, with dozens of tie-in issues across their entire line of comics, from The Amazing Spider-Man to Captain Marvel. The tagline, “Who Do You Trust?”, became iconic, perfectly encapsulating the story's paranoid tone. It was designed to be the climactic chapter of a long-form narrative Bendis had been building since he took over the Avengers franchise, resolving lingering questions about the illuminati and the state of the post-Civil War hero community.
The seeds of the Secret Invasion were planted decades apart in the two primary Marvel continuities, leading to vastly different motivations, scales, and outcomes.
The Skrull plan for conquering Earth has deep roots in their history and theology. Following the destruction of the Skrull Throneworld, Tarnax IV, by galactus, the Skrull Empire was thrown into chaos. Empress Veranke, a devout religious zealot, rose to power by citing a prophecy that declared Earth as the new Skrull homeworld. This religious fervor provided a powerful justification for what would become a holy war. The immediate catalyst for the invasion, however, was a direct confrontation with Earth's most powerful minds: the illuminati. After the destructive conclusion of the kree-skrull_war, the Illuminati (composed of `Iron Man`, `doctor_strange`, `black_bolt`, `namor`, `Mister Fantastic`, and `Professor X`) traveled to the Skrull Empire to issue a stern warning against any future aggression towards Earth. Their show of force backfired spectacularly; they were captured and intensely studied. From these powerful captives, the Skrulls learned everything they needed to know about Earth's metahuman biology, technology, and social structures. Most importantly, they extracted genetic material that allowed their scientists to create a new generation of “Super-Skrulls” that were completely undetectable by any psychic, magical, or technological means known to Earth's heroes. For years, the Skrulls methodically executed their plan. They placed sleeper agents in key positions of power, replacing figures like elektra of the Hand, Black Bolt of the inhumans, and several high-ranking S.H.I.E.L.D. and S.W.O.R.D. agents. The most impactful replacement was that of Hank Pym, a founding Avenger. This allowed the Skrulls to gain intimate knowledge of the Avengers' operations and technology from the inside. Their strategy was patient and brilliant: wait for the heroes to destroy themselves. Events like Civil War and World War Hulk did exactly that, leaving the hero community fractured, exhausted, and distrustful of one another—the perfect environment for the final phase of the invasion to begin.
The origin of the MCU's Secret Invasion is radically different, stemming not from imperial ambition but from a broken promise and a refugee crisis. As established in the film `Captain Marvel`, the Skrulls were not conquerors but victims of a genocidal war waged by the kree. In the 1990s, `nick_fury` and `Carol Danvers` promised to find the surviving Skrulls a new home. For over thirty years, that promise went unfulfilled. The Skrulls, led by `talos`, remained hidden on Earth, with many using their shapeshifting abilities to work for Nick Fury in his intelligence network. However, a younger generation of Skrulls, born as refugees and knowing only a life of hiding on a planet that was not their own, grew disillusioned and angry. This faction was radicalized under the leadership of Gravik, a charismatic and ruthless leader who believed Fury and Danvers had abandoned them. Gravik's philosophy was a dark mirror of the comic's imperial ambition. He argued that the Skrulls should not beg for a home but take one by force. His plan was not a massive, overt military assault but a covert war of terror and political manipulation. He intended to sow chaos among human nations, specifically by framing them for attacks on each other, to trigger World War III. In the ensuing nuclear holocaust, humanity would wipe itself out, leaving a radiation-scarred—but habitable for the radiation-resistant Skrulls—planet for his people to claim. He established a secret Skrull settlement called “New Skrullos” at a decommissioned nuclear plant in Russia, where he also began experiments to create Super-Skrulls using a machine called the “Harvest,” which contained the DNA of numerous super-powered beings. This transformed the MCU's Secret Invasion from a story of conquest to a tragic tale of desperation, radicalization, and the consequences of neglect.
The execution and consequences of the Secret Invasion diverged significantly between the comic book and cinematic universes, reflecting their different scales and narrative goals.
The comic storyline was a massive, sprawling war with multiple fronts and shocking reveals.
For years prior to the main event, Skrull agents replaced key figures. The first on-page sign was the defeat of Elektra by the New Avengers, revealing her as a Skrull imposter. This single act ignited paranoia across the superhero world. Subsequent investigations by the Illuminati revealed that their own member, Black Bolt, had also been replaced. The imposter was killed, but the damage was done—the heroes knew they had been compromised at the highest levels.
The Skrulls were defeated, but the cost was immense. The public's faith in its heroes was shattered. S.H.I.E.L.D. was seen as incompetent for allowing the infiltration to happen. In the power vacuum, the U.S. President disbanded S.H.I.E.L.D. and handed its resources and authority over to the man of the hour: Norman Osborn. Osborn rebranded S.H.I.E.L.D. into H.A.M.M.E.R. and formed his own team of “Dark Avengers,” consisting of villains masquerading as heroes. This began the Dark Reign era, where the villains were in charge, and the true heroes were fugitives. The paranoia of “Secret Invasion” was replaced by the open corruption of a world run by its greatest monster. The event permanently altered the political and social landscape of the Marvel Universe.
The MCU's version was a contained espionage thriller focused on a handful of characters.
Unlike the comics, the MCU infiltration was not about replacing heroes but about replacing key political and military figures to orchestrate global conflict. Notable replacements included:
While nuclear war was averted, President Ritson, now deeply paranoid, declares all extraterrestrial species on Earth to be enemy combatants, launching a global witch hunt. This creates a new, dangerous world for the million Skrulls still hiding on the planet, turning them from refugees into targets. Nick Fury leaves Earth with his Skrull wife, Varra, to try and broker a peace treaty with the Kree, finally attempting to fulfill his original promise. The world is left in a state of high tension, with humans now violently xenophobic and the Skrulls facing persecution, setting up future conflicts.
The true depth of the Secret Invasion event is found in its numerous tie-ins, which revealed the full scope of the infiltration and its impact on individual characters.
This crucial prelude one-shot tells the story of the Illuminati's disastrous trip to the Skrull homeworld. It provides the entire backstory for how the Skrulls were able to create their undetectable Super-Skrulls. It shows their capture, the experiments performed on them, and their violent escape, which planted the seeds for the future war. This issue is essential reading for understanding the “why” of the invasion.
After the invasion is over, Tony Stark and the real Jessica Drew confront the captured Veranke (still in Drew's form). In a shocking twist, Veranke reveals that she replaced Drew before Jessica joined the New Avengers. This meant that the Spider-Woman who had been a core member of the team, who had developed deep friendships, and who had even begun a romance with Hawkeye, was the Skrull Queen all along. This was one of the most personal and devastating betrayals of the entire event.
This tie-in series followed investigative journalist Ben Urich and his protégé Sally Floyd as they experienced the invasion from a civilian, street-level perspective. It provided a gritty, boots-on-the-ground view of the chaos, fear, and heroism of ordinary people caught in the crossfire. It grounded the epic conflict and explored the crucial question of how society functions when you can't trust anyone.
During the invasion, the original Kree hero Captain Mar-Vell seemingly returns from the dead. He is hailed as a messiah figure by the Kree. However, it is eventually revealed that he is a Skrull sleeper agent named Khn'nr, specifically programmed to believe he was Mar-Vell. In a tragic final act, his programmed personality breaks down, but the heroic Mar-Vell persona asserts control, and the Skrull agent chooses to fight and die for the Kree, the very people he was meant to subvert. This was a complex and poignant side-story about identity and heroism.
Beyond the main Earth-616 and MCU versions, the Secret Invasion concept has been adapted in other media.