In the grand scheme of the Marvel Universe, Secret Invasion might go down as the Skrulls' greatest accomplishment. In that monumental event, the shape-shifting aliens divided the Marvel Universe, sowing seeds of mistrust by infiltrating key organizations on Earth. But an entire decade before Secret Invasion, a small group of Skrulls managed to infiltrate Hydra, planting the seeds for their future conquest.

This infiltration took place in 1998's Captain America #3-7, by Mark Waid, Ron Garney and Dale Eaglesham. Three Skrulls, stranded on Earth, became high-ranking members of Hydra. Before long, their ring-leader took over the entire organization. This Skrull distinguished himself from other Supreme Hydras by declaring himself the "Sensational Hydra."

The Sensational Hydra enacted several major crimes with the hopes of grabbing Captain America's attention. Naturally, Steve Rogers triumphed over every obstacle Hydra threw his way.  Little did Captain America know, however, that this was exactly what the Sensational Hydra wanted. As he gained several victories against Hydra, Captain America also gained more of the public's trust.

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Sensational Hydra Reveals Himself as a Skrull and Impersonates Captain America

When the time was right, the Sensational Hydra and his cohorts ambushed Captain America, revealing themselves as Skrulls. The former Sensational Hydra then took Steve's place, impersonating the Star-Spangled Avenger. "Captain America" then staged an assassination on the President of the United States before saving the president himself. Exposing his cohorts, this impostor declared that Skrulls had infiltrated the entire planet. Taking advantage of Captain America's trustworthy image, the Skrull sent Earth's citizens into a violent panic.

This feat was quite impressive, as the Skrull built up Captain America's image just so he could use him to destroy human civilization. Eventually, however, the real Captain America got Tony Stark and Reed Richards to create a device that exposed the impostor. With the combined power of the Avengers and the Fantastic Four, Steve took down his replacement before giving a rousing speech where he reminded Americans that he served them, not the other way around.

This whole storyline set the stage for Secret Invasion nearly a decade before the actual event began. The Skrull who replaced Captain America enacted the basic plot of Secret Invasion, albeit on a smaller and more condensed scale. Rather than replacing several major figures on Earth, the Skrulls specifically chose to replace Captain America. Still, the overarching idea remained the same in both stories, sowing seeds of mistrust within the public and tearing humanity apart from the inside. This initial storyline wasn't as successful as Secret Invasion, but it came fairly close. Considering the panic which the Skrulls incited, replacing Captain America proved to be very effective.

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A Skrull Impersonates Captain America and Incites Panic

Even the real Captain America could barely get the situation under control, as Earth's citizens were unsure of who to trust. Even after the dust settled, it was hard for Steve to regain his public image. Interestingly enough, this was also a sort of precursor to Secret Empire, where an impostor, posing as Captain America, used his influence so that Hydra could take over the United States of America.

Years later, both during and after "Secret Invasion," it would be even more difficult for the public to trust heroes like the Avengers. Another precursor to "Secret Invasion" came shortly afterward, in 1999's Uncanny X-Men #371, by Alan Davis, Terry Kavanagh and Jim Cheung. This issue saw Wolverine replaced by a Skrull impostor, while the real Logan was captured by Apocalypse and turned into his Horseman.

Just like Captain America's replacement, this situation led to much internal conflict and mistrust. Of course, this wasn't part of a Skrull plot, making it fairly harmless compared to Captain America's replacement or Secret Invasion. Regardless, replacing heroes such as Captain America and Wolverine only served as the first steps leading to the Skrulls' inevitable invasion.

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