The first movie that's been officially announced by Marvel for their phase three plan is Edgar Wright's Ant-Man. It will be the first movie we see after The Avengers 2. That being the case, I think it's safe to assume that Ant-Man will be a part of The Avengers sequel.
Wright has been working on the script for Ant-Man since before the first Iron Man movie was made. Since then, the Marvel cinematic universe has grown, and Kevin Feige has revealed that the script is going through a re-write so that it can be fit in with the rest of the universe. When talking to EW he said,
Frankly, now we have to re-write it to put it a little bit more into the [Marvel Cinematic Universe] because it was written before it existed.
As most of you know, there's some test footage that's been screened for the film at certain conventions and film festivals, it even leaked out online at one point. If you haven't had the chance to see it, take my word for it when I tell you it's awesome.
Wright is anxious to start shooting the film, which is scheduled to start next year. They have yet to cast the lead role though, and here's what he had to say about that...
We’ve talked about various names over the past eight years but as you can imagine they keep changing as time goes by. But towards the end of this year, we’ll buckle down and start casting and start refining the script, which is great and which is very Edgar. He has done a great job being incredibly true to the comics but is putting his own spin on it, so we’ll be drawing on multiple mythologies for this one.
As silly as an Ant-Man movie might sound, it's going to be crazy entertaining. Especially with Wright at the wheel. When talking about the test footage that was shot Feige says,
Sometimes we take it for granted that people know what we’re doing, Some people don’t get it: ‘Ant-Man …? Is that goofy? What? He talks to ants? What is this…?’ The test real fixes that, Feige says: “Then they suddenly go, ‘Ohhh…’
Ant-Man is scheduled to hit theaters on November 6th, 2015!