WARNING: The following contains major spoilers for The United States of Captain America #4, available now from Marvel.

The United States of Captain America has seen Steve Rogers and Sam Wilson travel across the nation, meeting various other Captains in their search for the villains who are out to tarnish that good name. Along the way, they have learned of an entire network of underground Captains, all of whom are in grave danger now that they've adopted the moniker. While most of these independent heroes are far from super soldiers, not all super soldiers are heroes, and Warrior Woman has just returned to remind the world of that fact in The United States of Captain America #4 by Christopher Cantwell, Ron Lim, Cam Smith, Scott Hanna and VC's Joe Caramagna.

Steve, Sam and Bucky Barnes have all made their way to Colorado in their search for answers. Despite all their hard work, they haven't made much headway in hunting down the false Captains who are out to destroy Steve's legacy. Thankfully, the heroes have just been given one lead that is impossible not to follow, even if it does come with the arrival of another powerful villain to worry about. At NORAD's Cheyenne Mountain Complex, an explosion rocks the foundation, and from the flames emerges Sin and Speed Demon led by Warrior Woman.

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Julia Koenig aka Warrior Woman first appeared all the way back in 1977's Invaders #16 by Roy Thomas and Jim Mooney. As a Nazi spy during World War II, Koenig was captured and fell under the hypnotic influence of Joseph White, the one man who held the secrets to the Super-Solider Formula. After regaining control of her own mind, Koenig tested the formula on herself, and although the process ended in disaster, Julia survived to become one of the first true super-soldiers. Hitler became fascinated by Koenig's transformation, dubbing her his "Krieger Frau" and she was paired with the superpowered Master Man to murder the Invaders. Even though it has been nearly a century since then, Krieger's dedication has never waned, and her return has all been in the name of bringing back her true master as well.

In this issue, the villainous Krieger comes across the original Hate-Monger, Adolf Hitler himself, trapped within some sort of prison capable of holding his incorporeal form. Through her hypnotic abilities, Krieger has manipulated Speed Demon into helping her and Sin carry out their true mission. When the assembled Captains America finally show up, she is quick to turn those same powers on them, but Steve Rogers gets the jump on her before she can do too much damage. As two of the few true super-soldiers to come out of Project Rebirth, Warrior Woman and Captain America have a special sort of loathing for one another, as each sees the other as a twisted reflection of themselves. It is that resentment that makes Julia so quick to lash out when referred to by her old moniker, one which she openly considers to be ludicrously infantile. Where Warrior Woman is unable to take any pride in her title, Steve Rogers knows all too well what his means, and letting her take that away isn't an option.

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While Krieger and Hate-Monger are ultimately able to slip away, the fact that they have returned at all is a shocking development in itself. There aren't many more classic Captain America villains in the history of Marvel Comics, and certainly none with whom he shares such an intense hatred. Now that Krieger has set loose Cap's worst enemy, there is no telling how much damage the two will be able to do before the heroes can catch up to them. Here's hoping it isn't more than the United States of Captain America can handle.

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