Secret Invasion is promising a “Cold War espionage” style thriller on an intergalactic scale. The Disney+ series will deliver a clandestine battle for the very fate of Earth, where not even the world’s greatest spy can know the identity or allegiance of those around him. The show won’t be able to truly deliver a story worthy of its premise, however, if the only secret Skrulls we meet are entirely new characters. It won’t surprise anyone if Olivia Coleman’s MI-6 agent is actually an alien plotting to destroy mankind. It won’t mean all that much, either.

For Secret Invasion to truly have an impact it will need to reveal people we already know and trust have always been hiding their real identity. But which long-time characters would make sense without retcons if the MCU suddenly unmasks them? The show will feature two stalwarts that fit all the criteria needed.

Each has reached the highest levels of the U.S. government. That’s something Skrulls did in Marvel Comics, just as they’ve already done in the MCU. They’re also two characters whose personal lives we know shockingly little about: Colonel James “Rhodey” Rhodes and Everett K. Ross and.

Don Cheadle looks forlorn as Colonel Rhodes split with MArtin Freeman in a t-shirt as Everett K. Ross
Marvel Studios

Secret Invasion will almost certainly feature characters replaced by Skrulls. That happened in the comics all the time. That will also be part of the reason why Nick Fury needs to fight this war “alone,” but maybe not the most important one. Even the world’s greatest spy won’t know who his true friends really are.

Anyone and everyone he meets on the show might be an alien double. But in terms of characters who have secretly been Skrulls their entire time in the franchise, the choices are limited. Technically his closest confidant, Maria Hill, qualifies. Only we’ve already seen her willingly replaced by a Skrull in Spider-Man: Far From Home. Marvel now saying the “real” Maria is also a shapeshifter would fall flat. And since nothing in Captain Marvel makes sense if Nick Fury himself is a Skrull, that leaves only two main candidates who a) could have been aliens since their introduction and b) would qualify as genuinely shocking. Their stories thus far also happen to make perfect sense for such a revelation.

What do we really know about either Colonel Rhodes or Everett Ross beyond the jobs they have? We’ve never seen much (if any) of their personal lives. We also know almost nothing about their pasts. The most significant fact we’ve learned about either is Ross was once married to the shadiest person in the US government.

His ex-wife is current Deputy Director of the CIA Valentina Allegra de Fontaine. In the context of Secret Invasion, that lone personal fact is actually incredibly damning. The only person Ross has had a private relationship with is someone who tries getting Avengers killed. Doesn’t sound like they had the most honest marriage in history. What might he have been hiding from her? (And yes, a Skrull temporarily replaced Val in Marvel Comics.)

Marvel Studios

Both Rhodey and Ross are essentially complete mysteries beyond what they do. But what they do—and, just as importantly, who they do it with—is fascinating in the hunt for secret Skrull candidates. They each attained important positions in the U.S. government without garnering the kind of spotlight someone in hiding would want. They’ve wielded enormous power in the military and CIA without ever being anyone’s focal point. They work alongside and advise some of the most powerful people in the world. And while Ross is on the run after Black Panther: Wakanda Forever, Secret Invasion will find Rhodes now serving as the “right-hand man” to the President.

These are smart people who don’t just know the world’s two biggest superpowers’ most important and biggest secrets, they have/had the ability to act on them, either directly or indirectly. They are exactly the type of characters—highly capable figures we know little about who can avoid intense media or professional scrutiny—who make perfect sense to be Skrulls even though it will be completely shocking to discover their real identity.

Marvel Studios

If either or both ultimately is revealed as a Skrull, that won’t change the fact they served humanity and Earth loyally before. Neither will it mean they won’t do so now. Ben Mendelsohn’s Talos is a Skrull we know about who’s done just that. As have other Skrulls who’ve been secretly working for Nick Fury. Instead, their past actions will make the truth about their real identity even more meaningful now.

Every member of that alien race, even those who have protected and fought on Earth’s behalf for decades, will face a choice. They will have to choose a side in a war that will pit their own kind directly against mankind.

We know from the show’s trailers Nick Fury doesn’t want the Avengers to help him in this battle. His refusal to call Earth’s mightiest heroes shows Fury can no longer trust anyone when an army of shapeshifters are out to get him. But it also suggests he doesn’t want anyone getting involved because he can’t be sure who any Skrull will fight for when the time comes.

Whether he already knows someone like Everett K. Ross is really a Skrull, or has no idea someone like Colonel Rhodes is, the best way for Nick Fury to make sure he never has to worry about anyone’s allegiance is to make sure they don’t have to pick.

When you’re fighting to save Earth from an enemy that can take on any identity they want, you can’t trust anyone you meet. Not even heroes fans of the MCU thought we truly knew this whole time.

Mikey Walsh is a staff writer at Nerdist. You can follow him on Twitter at  @burgermike. And also anywhere someone is ranking the Targaryen kings.