Be warned, if you haven't seen Captain America: The Winter Soldier yet, there will be HEAVY SPOILERS contained below, so read on at your own risk. If you have seen the latest Marvel Phase Two adventure, producer Kevin Feige revealed new information about how this movie ties into upcoming movies Doctor Strange and Avengers: Age of Ultron in an interview with Crave Online.
There is a brief scene in Captain America: The Winter Soldier where Agent Sitwell (Maximiliano Hernández) mentions Dr. Stephen Strange a.k.a. Doctor Strange, as one of the targets of Project Insight, which uses an advanced algorithm to determine which individuals with certain talents need to be spied on by the government. Of course, a Doctor Strange movie has been in development for quite some time, and when asked what this reference meant, Kevin Feige had this to say.
"Well, 'we' know what it means and where we want to head with it, but we were comfortable with keeping it in there and leaving it in there because there are a few different ways to interpret it. The whole thing, what Sitwell's saying is, this algorithm is going to predict if you're going to become a problem for Hydra or not. So you don't have to just be Tony Stark, actively plotting to save the world. You could be a kid whose SAT scores and whose essays have indicated that you're going to be a problem one day. So is Stephen Strange the Sorcerer Supreme? Probably not at that point. Is he an unbelievably talented neurosurgeon who's opinionated and kind of arrogant? Probably. That might put him on the list."
There is also another reference in the movie to Clint Barton, a.k.a. Hawkeye (Jeremy Renner), when a S.H.I.E.L.D. agent wonders what he is up to. Kevin Feige revealed there will be an answer to that question in next year's Avengers: Age of Ultron.
"We will discover, later, the answers to that question. But it really came down to how many players can you have on the field at this time? We really wanted to bring in Falcon, we really wanted to team [Captain America] up with Black Widow, we really wanted Fury to have more of a part than he's ever had in any of the other movies before. We wanted, ever so briefly, to introduce Sharon Carter. And we had a fun place for Maria Hill to be involved. So we didn't want to just have, 'Hey, I'm Hawkeye! Hey, I'm Iron Man!' We want to avoid the brief cameos of the week. Not every character from every movie is going to be in Avengers: Age of Ultron, for sure. But Joss (Whedon) is excited and, for the characters you haven't seen since the first Avengers - like Hawkeye, like Hulk - there's a reason for that, and that gets showcased quite prominently in AAvengers: Age of Ultron."
Be warned, MAJOR SPOILERS are ahead! Kevin Feige also spoke about the destruction of S.H.I.E.L.D., which we learn has been infiltrated by Hydra the whole time and is essentially destroyed from within by Cap, Falcon and Black Widow. Kevin Feige revealed where the origin of that plot point came from.
"It was a combination. I mean, I've been thinking since the first Captain America film that if the SSR was a... you know, the SSR was the organization that Captain was a part of in the first movie, and had the super soldier program. That was basically our version of the precursor to SHIELD, which in real life there was... I forget what it was called now, but there was a division that was a precursor to the CIA in real life, and in real life there was Operation Paperclip, which Widow mentions. They worked with Nazi scientists and Nazi equipment, and that's part of where NASA came from. I had this thought for a long time that the SSR defeated Hydra, brought in their scientists, brought in their weaponry, that's what SHIELD was founded on. But what if there was more to that than meets the eye? In Avengers, Captain America finds a Hydra helmet, Hydra weapons, and realizes that SHIELD has this whole plan Nick Fury was even aware of, of taking Hydra weapons and building them again. So I thought, what if SHIELD was Hyrda?"
"One of the first people I ever pitched that idea to was Chris Evans, on the set, on the very last day of production of Avengers 1. We were in Central Park and he goes, 'So, part two, what are we doing?' I said, 'Well, we've got a lot of ideas.' Winter Soldier was a big idea for it. And I said, 'I have this idea for SHIELD.' He said, 'You're blowing my mind! That's amazing!' I thought, 'Well, maybe it is good. Let's try that. We also got excited... The TV show didn't exist when we were starting this. But they were well aware of what was happening, because I said 'This is what we're doing.' The other thing that we thought would be fun was using this to change the dynamic for The Avengers, so that the safety net - if you can call it that - of a giant government organization with massive resources, of which they were just sort of the front, or the A-Team at the head of that organization... take all that away. So when they come together in the next movie it's just them."
The sequel also touches on some real-life issues of the government spying on Americans, mirroring the Edward Snowden scandal.
"What's funny is all of that storyline was absolutely inspired by those kinds of beats in the comics, when he found himself up against the country and the government. But what we're really doing is, it's SHIELD. It's a made-up organization. It's helicarriers. And I'm sure you've heard already that we were midway through filming, we had shot all of those scenes, the script was done, when that NSA/Edward Snowden thing happened. We went, "Holy..." I said, "Look, there are helicarriers here with all sorts of... They're listening! It's SHIELD! That's what Cap's fighting against!" We couldn't believe it. And if that has heightened the focus on this film and Cap's actions in this film, all the better. But it legitimately all started [with] what's the best conflict we could throw Cap into that would make the coolest action movie. But the fact that it hit something, purely coincidentally, that was so relevant was pretty amazing."
Finally, one of the end credits scenes features Loki's scepter, which has lead to speculation that it may be one of the Infinity Gems.
"Well, it's certainly pure speculation at this point. I'm not even sure if we even recognize Loki's scepter [as an Infinity Stone], but that's a big hint as to what will be causing them trouble in the next movie."