Marvel's Secret Invasion - what you need to know

2008's Secret Invasion is one of Marvel Comics' most impactful stories of all time, with the crossover event nearly encompassing the publisher's entire monthly line along with a host of tie-ins specials and series. And now that story of a hidden infiltration of shape-shifting Skrulls in the Marvel Universe is coming to the MCU as the next Disney Plus streaming series that brings back Samuel L. Jackson's Nick Fury, Cobie Smulders' Maria Hill, Ben Mendelson's Talos, and more.

Given the original comic book story's daunting size and nature (which you can more easily navigate with our handy Secret Invasion reading list), it's likely that the MCU Secret Invasion won't touch all the story points of the event that inspires it. But on the other hand, if the MCU adaptation is even a little bit like the comic book Secret Invasion, it can still have a massive, potentially devastating impact.

So what is the story of the comic book Secret Invasion? What roles do Nick Fury and Maria Hill play in the original? And which superheroes and supervillains are replaced by shapeshifting Skrulls?

The invasion may have been a secret, but the answers to these questions aren't - and we've got them right here.

What happens in Secret Invasion?

During a fight between the New Avengers and the evil ninja group known as the Hand, Echo of the Avengers stabs Elektra (then under the control of the Hand) in the chest, killing her. But when the life leaves her body, it's not Elektra laying there - it's a shapeshifting Skrull, who was apparently hiding in the Marvel Universe, operating as Elektra for an unknown period of time.

An autopsy on the Skrull reveals she possesses advanced, genetically engineered shapeshifting abilities beyond what Skrulls have previously been shown to display, including the ability to mask even their thoughts from psychic intrusion, and a way to disguise their Skrull DNA as human, allowing them to bypass nearly all known methods of discovering shapeshifters in the Marvel Universe at that time.

As for why the Skrulls are invading, it's due to a series of events stretching back years in the Marvel Universe (and decades of real-world time), all the way back to the classic '60s Avengers story The Kree/Skrull War, which established the concept of the war between the Kree and Skrulls. After decades of fighting both the Kree and Marvel's heroes, the Skrull then suffered a major blow in the 2006 crossover Annihilation, in which Galactus destroys the Skrull homeworld. 

Turning to their ancient prophecies, the Skrull decide to take over Earth, believing it to be their new homeworld as foretold in their legends, enacting their long-term Secret Invasion (there's the title of the story!) of Earth.

Back in the present day, the discovery of the Skrull kicks off a chain of events revealing that Skrulls have infiltrated numerous aspects of human society, including replacing several heroes outright (more on that in a moment). 

Both teams of Avengers, who were split into two teams due to the ideological conflict of the event Civil War, become suspicious of the members in their own ranks. Nick Fury, who has been in hiding, reveals that he knew of the Skrull invasion and has been planning his own counterforce. And finally, the Skrulls begin their full-on invasion of Earth, starting with mining Vibranium in the hidden prehistoric world of the Savage Land.

There, both teams of Avengers and the Fantastic Four confront the Skrulls, as Reed Richards devises a new method to detect which of them are shapeshifters. In the fight, a whole Skrull ship full of heroes arrives, all of whom claim they are the original versions of the heroes and have been held captive among the Skrulls for years, claiming that their modern-day counterparts are Skrull imposters.

But most of them are lying, with only a few heroes actually returning from Skrull captivity, while the rest are infiltrators attempting to sow discord among the heroes to aid the invasion - which ramps up with a series of major attacks following the Savage Land fight.

Which heroes are replaced by Skrulls in Secret Invasion?

Before we get into what happens when the Skrull invasion goes full-scale, we'll run down which heroes are actually replaced with Skrulls, which ones are only temporarily replaced, and which ones have to face off with their own Skrull doubles.

First and foremost, there's Elektra, the hidden Skrull whose discovery kicks off the story. As it turns out, Elektra was replaced around the time of the 2005 story Wolverine: Enemy of the State, meaning there was a Skrull Elektra secretly running around the Marvel Universe doing Elektra stuff for years.

Second, there's Spider-Woman. In one of the story's first major twists, it's revealed that the Spider-Woman who has been a member of the New Avengers for years is, in fact, Veranke, the Skrull Empress, in disguise - and she's been impersonating Spider-Woman for years, engineering the Secret Invasion of Earth from behind the scenes, and even using the revelation of Elektra as a Skrull to push her own agenda forward.

There's Black Bolt, who was replaced at an unknown point, infiltrating the secret group the Illuminati. And there's Contessa Valentina Allegra de Fontaine, who was replaced sometime after the story Secret War, spying on Nick Fury - which is partly how he becomes aware of the invasion.

And then there's Hank Pym, who was replaced sometime before Civil War - and whose infiltration has deadly consequences for another Avenger (more on that in the next section).

The last major character to be fully replaced by a Skrull is Mockingbird, the ex-wife of Hawkeye. As it turns out, Mockingbird's abduction by the Skrulls goes all the way back to the late '80s when she and Hawkeye were falling in love as part of the West Coast Avengers. The Skrull who replaced Mockingbird actually died way back in the mid-'90s - in the finale of West Coast Avengers - but her body wasn't discovered.

As Hawkeye tragically finds out, the Mockingbird he married and mourned wasn't actually the woman he had fallen in love with, but a Skrull - and the real Mockingbird has been locked away in a Skrull prison for years, with no knowledge of their supposed marriage or her own apparent death.

Many other heroes are temporarily impersonated, especially in the previously mentioned Savage Land fight where a large group of Skrull impostors crashes and tries to infiltrate the heroes.

These include:

• Yellowjacket
• Captain America
• Dum Dum Dugan
• Edwin Jarvis
• Captain Marvel (Mar-Vell)
• Invisible Woman
• Elektra
• Emma Frost
• Beast
• Spider-Man
• Luke Cage
• Thor
• Wonder Man
• Jean Grey
• Iron Man
• Hawkeye
• Vision
• Jessica Jones
• Scarlet Witch
• Mockingbird
• Wolverine
• Carol Danvers

How does Secret Invasion end?

After the reveal of the Skrull hero imposters and the Skrull invaders posing as important human leaders, the Skrull invasion goes into all-out war, with attacks on the SHIELD Helicarrier, the Thunderbolts headquarters, the Fantastic Four's Baxter Building, and the supervillain prison the Raft.

A whole army of Super-Skrulls - Skrulls who are engineered to have the powers of multiple Marvel heroes such as the original Super-Skrull, Kl'rt, who has all the powers of the Fantastic Four - are dispatched around the globe. These include several Super-Skrulls with the powers of multiple X-Men such as Colossus, Wolverine, and Nightcrawler, as well as Super-Skrulls based on the Avengers.

The fight escalates into a series of conflicts that engulfs almost the entire Marvel Universe (our Secret Invasion reading order is a perfect guide to which tie-ins and stories are essential to the crossover, by the way), while Nick Fury and his Secret Warriors, both teams of Avengers, the X-Men, the Thunderbolts, and the Fantastic Four, and more heroes all fight against the impossibly powerful Super-Skrulls - as well as the villain the Hood and his gang of dozens of supervillains, who join the side of the heroes to save Earth.

As the heroes finally start to gain the upper hand, Veranke activates her final weapon - a weaponized strain of Pym Particles that the Skrull posing as Hank Pym has secretly used to turn Janet Van Dyne, the Wasp into a living bomb. 

Janet begins to grow uncontrollably, threatening to destroy the entire area and everyone in it in a massive blast. Thor manages to use his cosmic might to contain the explosion, but Janet still dies.

Almost beaten, Veranke tries to rally - but she's suddenly shot dead on the spot using a special weapon wielded by Norman Osborn, the former Green Goblin and leader of the Thunderbolts at the time, which was built using Skrull tech stolen by Deadpool.

Veranke's death ends the fight, and the real Elektra, Hank Pym, and others are returned.

In the aftermath of Secret Invasion, SHIELD is disbanded and Norman Osborn is made the leader of a new organization named HAMMER. The Avengers reconcile after the events of Civil War and begin working against Norman Osborn, who assembles his own Dark Avengers to take their places as Earth's Mightiest Heroes. And Hank Pym temporarily takes on the codename 'the Wasp' in honor of Janet's memory.

This leads into the 'Dark Reign' era of the Marvel Universe in which Norman Osborn and HAMMER try to bring Earth to its knees on their own terms - but that's a story for another time.

Marvel Comics recently launched a new Secret Invasion comic book series, but given the MCU Secret Invasion was filmed months ago, it seems unlikely story elements will carry over, but if you can check out here for the latest surprise spoilers.

Secret Invasion in the MCU

Right now, we know only a bit about the MCU version of Secret Invasion. The six-episode streaming series focuses on Nick Fury as he uncovers a Skrull invasion plot spinning out of the end of Captain Marvel, in which some Skrulls, such as Ben Mendelson's Talos who also appears in the streaming series, became refugees.

But we don't know which (if any) MCU heroes will be revealed as having been replaced by Skrulls in the show, let alone how big the conflict will get.

One thing we can count on is that the idea of Skrulls hiding in plain sight will be at the heart of the story, and that could signal some clues about who might be a Skrull. 

The character who could be the most important from the original comic book Secret Invasion may be Julia Louis-Dreyfus' Contessa Valentina Allegra de Fontaine, whose enigmatic presence in the MCU has hinted at a much bigger conflict on the horizon. 

She'll play a role in the upcoming Thunderbolts movie, which could be significant as both the team and Contessa played important parts in the comic story. Contessa seems to be replacing Norman Osborn as the team's manipulative handler - so could she also take his role in Secret Invasion? Or could she be a Skrull, as in the comic story?

The layers of questions will likely only grow in anticipation of Secret Invasion's 2023 premiere.

Secret Invasion is one of the best Marvel Comics events of all time.