I'm pretty sure this is old news (probably at least been speculated since Iron Man 3), but I'm going to say it anyway in case anyone missed it. (This post contains potential spoilers for those of you who want them. If you don't, then you probably shouldn't read anymore)
So if you saw Iron Man 3, you probably remember this chick:
This is Ellen Brandt, the A.I.M. Extremis agent who tried to kill Tony Stark while he was in Tennessee. But Ellen Brandt is bigger to the Marvel Universe than just a soldier who gets blown up and strung from telephone wires. In the comics, Ellen Brandt was the wife of Dr. Ted Sallis, better known as Man-Thing.
First, a little bit of back-story on the Man-Thing:
Young biochemist Dr. Theodore "Ted" Sallis, a native of Omaha, Nebraska, is working in the Everglades as part of Dr. Wilma Calvin's Project: Gladiator team, which includes Dr. Barbara Morse and her fiancé Dr. Paul Allen. A Dr. Wendell is later cited as being on the staff after Dr. Calvin is shot. The group is attempting to recreate the "Super-Soldier Serum" that had created Captain America... ...Though warned that the technological terrorist group Advanced Idea Mechanics (AIM) has been operating in the area, Sallis breaches security by bringing with him his lover, Ellen Brandt (referred to here as "Miss Brandt", but later retconned to be his wife). He destroys his notes to his formula, which he has memorized. Later, he is ambushed and learns Brandt has betrayed him. Fleeing with the only sample of his serum, he injects himself with it in hopes of saving himself. However, he crashes his car into the swamp where chemical and, as Man-Thing #1 later explained, magical forces instantly transform him into a slow-moving plant-matter creature with large, solid red eyes, unable to speak, and with dim memories, he attacks the ambushers and Brandt, burning and scarring part of her face with an acid he now secretes in the presence of violent emotions. The Man-Thing then wanders away into the swamp.
-Man-Thing's Wikipedia page
Rumors that Man-Thing would be appearing inevitably started rolling after Ellen Brandt appearing in Iron Man 3 as an A.I.M. operative, (and if you look closely, you can see the scars on her face that were given to her by Man-Thing. Go back up and take a look.) but those rumors were basically confirmed on Tuesday during Agents of S.H.I.E.L.D. episode Nothing Personal. In the beginning of the episode, we see Maria Hill talking on the phone to Pepper Potts. She says:
Yeah, it went as expected. S.H.I.E.L.D. implodes, and everyone wants answers. The C.I.A, N.S.A, and N.R.L., them I can handle, but Congress…Congress is like kindergarten. Where is this Fridge? What was in there? And who or what is a Man-Thing?
So that means that Man-Thing was most likely in the Fridge, and was broken out when Ward and Garrett raided it. This doesn't necessarily mean that he is working for HYDRA. If he were, then I don't think Congress would even know he existed, and therefore would not be asking Maria Hill about him. The more likely scenario is that he is simply trying to get back to his home in the Everglades, and somebody saw him and reported it.
Overall, I think that this means that it's fairly safe to say we'll be seeing some of Ted Sallis onscreen at some point. Or could these just be throwaway easter eggs, like the map of Antarctica in Howard Stark's stuff in Iron Man 2 (reference to the Savage Land, where vibranium was discovered)? I think it would be really cool to see Man-Thing somewhere, and they've definitely pointed several hints that way too. Sorry if this is all old news, but I haven't seen anything about it on here yet.
What do you guys think? Is this a smart play for Marvel, or a big mistake? Do you like the idea of seeing the Man-Thing, or is there someone else you'd rather see?