[SPOILER WARNING: Mild spoilers for "Agents of S.H.I.E.L.D."]

For a long time now, murmurs of the word "Inhuman" have circulated through the Marvel Cinematic Universe fandom, particularly surrounding Marvel Comics' recent "Inhuman" launch, Vin Diesel's tease that he may be playing Black Bolt, and the fact that Fox currently controls the rights to X-Men characters and related mutants (thus excluding this element from the MCU). However, none of that may be as convincing as what's going down on "Marvel's Agents of S.H.I.E.L.D." -- and here's why.

Here's my biggest piece of evidence: Coulson's alien writing. Now, ever since he discovered that it's experimentation with alien blood that resurrected him, he's taken to carving a strange "alien" language, as follows:

I've been puzzling over this for some time now, because I thought it looked familiar but I couldn't remember where I'd seen it before, because I read a lot of different comics. But then it hit me:

Look closely at the first few letters, particularly "INHU." Although they certainty aren't identical, there are a lot of similarities between the symbols in the logo and Coulson's writing.

These aren't your mama's Inhumans.

As we've seen, the MCU doesn't follow comics to the letter. I mean, really, who could, with source material that stretches out for decades? Joss Whedon's "Avengers" film even blends elements from the "Ultimates" universe in with the main Marvel U's trappings. As such, it makes sense that the MCU definition of Inhuman is a little different than what we see in the comics; it's not going to play by the same rules. And, since it's not playing by the definition laid down in the source material, who's to say humans couldn't engineer Inhumanity for themselves? Or, on the other hand, why couldn't it be possible for humans to recreate an experiment that the Kree may have already performed?

But how do we know the Kree were involved?

The body in the tube -- the one Coulson discovers, much to his horror, is almost definitely a member of the Kree race. Although we could only guess at this at the time of the episode's release, "Guardians of the Galaxy" gave us a pretty good look at healthy, walking, talking Krees. The body in the tube is certainly emaciated (who knows how long it was in there? or even what state he was in before he was captured?) but the similarity between the body and the Kree citizens we saw in "Guardians" is pretty striking.

How does this play into the larger MCU?

Easy. Do you remember the after credits sequence from "Captain America: The Winter Soldier" with Scarlet Witch and Quicksilver? They're a good candidate for the first powered Inhumans we see in the MCU. Obviously, they can't be mutants and they can't be the children of the on-again-off-again villain Magneto, whose rights are firmly locked at Fox. So how do we spin this for the MCU? This sequence gave us a glimpse of Baron von Strucker, a HYDRA agent and longtime Captain America villain. In the comics, von Strucker has children -- a set of twins, a boy and a girl, who were experimented on by HYDRA and had their own super powers. They become super villains themselves and operate under the name Fenris. Change the mythos around a little, and Wanda and Pietro could easily substitute as von Strucker's evil progeny. Utilizing the same procedure that brought Coulson back to life, they too could have been infused with Kree blood/genetics. What's more, von Strucker and his HYDRA scientists could have invented (or reinvented) terrigenesis, which would grant Wanda and Pietro their super abilities -- and perhaps make them a little unstable. Wanda and Pietro could be the first of many such powered Inhumans, as Coulson and Skye both seem to be affected by the same transfusion.

But Nick Fury/Garrett would have known!

Not necessarily! Nick Fury, for all his experience and knowledge, didn't know about HYDRA. What's more, a team, no matter how small, must have worked on Coulson as he underwent this procedure. Who's to say a member of this medical team wasn't associated with HYDRA in some way? Who's to say the procedure wasn't invented by HYDRA themselves? It certainly isn't below HYDRA to toy with human lives for the sake of advancement.

And John Garrett? Well, it doesn't seem as though Garrett -- for all his talk -- was exactly in line to be the head of HYDRA. He's only one of the branches, albeit a powerful member of his branch. It's entirely possible HYDRA, in its compartmentalization, sent Garrett as their errand boy, there to pick up the package rather than to use it himself. Garrett was full of bravado and acted as a double agent for years; it's hard to take anything he says at face value. There's a lot of wiggle room there.

Where do we go from here?

Good question. This is a fan theory, gathered over the bits and pieces of evidence scattered throughout the MCU. "Agents of S.H.I.E.L.D." seems to be gearing up to answer these questions for us, of course. In the last episode, Raina talks about how she yearns to see "what we'll become." It hints at a change -- maybe metaphorically, but I think literally. HYDRA's experimentation could go a long way, especially considering how little we actually know about them and how widespread they are. Or, perhaps, they have nothing to do with it -- maybe the comics origin holds, and the Kree did pay earth a visit back in the day, leaving behind thousands of dormant Inhumans, waiting for the day that terrigenesis is unleashed upon the world, and that S.H.I.E.L.D./HYDRA's manufactured Inhumans are a fluke. Perhaps Black Bolt and Medusa already rule in secret on the dark side of the moon, silent and watching, aware that these dormant Inhumans may or may not manifest their powers.

We'll just have to wait and see.

A version of this article originally appeared on Meagan Damore's Tumblr and has been reprinted with permission.