When Marvel's The Avengers hit theaters in 2012, it was a resounding success, taking in over $1.5 billion at the box office worldwide, with some proclaiming it to be the best superhero movie ever. Of course, Marvel's The Avengers was just the beginning, with Marvel rolling out a slew of sequels and new adventures in Phase Two that lead up to Avengers: Age of Ultron, which has already earned $881 million worldwide in less than two weeks. While the sequel is certainly a financial success already, director Joss Whedon isn't coming back to Marvel anytime in the near future, even deactivating his own Twitter account following the sequel's release. The filmmaker revealed in a new interview that, while he said that Kevin Feige and everyone at the studio was "great," the process also broke him.

"You know, they were great. Because Kevin knows what he wants, he understands what I do. But I pushed them. I said, 'We're going to have these crazy dream sequences. We're going to go to a farm and hang out for a while. We're going to do some things that are really left of center. We're going to give you more action than you've had in any of your movies. We're going to give you a bigger movie than you've had. But. I'm also going to get a little funky. I was kind of ambitious with this. Again, I'm going to have a long scene where we talk about being sterile in the middle of an action movie. Some of it was a fight, and some of it wasn't, because they said, 'OK, you know what? We're terrified, but you know, you've earned this.' There are battles I lost, there are battles I won, but most of it was you know, was us just going, 'We're just going to keep working this, just keep working the problem and making it better." And I had Jeff [Ford] and Lisa, my editors for the first one, who are just mavericks and are very responsible for the stories making any sense at all. Those two, they saved my life so many times. They're storytellers. It's a beautiful thing to behold. It's weird because the first one was very, very, very, hard. This one was much harder. It a little bit broke me."

He added that, while the production did run smoothly, he had a much harder time on the sequel overall, stating that he even started to doubt himself while working on various aspects of the movie.

"So this time, there was a lot more understanding and trust going in, and my crew in England was phenomenal, but then the weight of the thing, the weight of the last thing, of this not just being the next thing that happens - I wanted this film to be its own movie. I wanted it to be better, if possible, than the first one - not that the first one was the best movie ever made, but I wanted to do better, just be better at shooting. I wanted to work harder on the script. I wanted to spend more time just really working every aspect of it, because why go again if you're not doing something new? And I shot it very differently, and all of that became sort of a burden where I was like, 'I want to make something great!' And then I heard that voice in my head every time, 'But is this a great idea?' And suddenly I had doubt that I don't usually suffer from. And meanwhile, the studio's gonna have some too, because everything's riding on this all of a sudden. And it became a problem in a way that nothing else has. And it was a hard movie to make on top of that. So being paralyzed by either indecision or the weight of responsibility? Not useful, don't have time for your paralysis, son, snap out of it. This was the hardest work I've ever done. And if it worked, yay! But I'll always look at it and go, 'I don't know, Joss, could you have done better? You could have done better.'"

As you may recall, right after principal photography wrapped on Avengers: Age of Ultron, the director shot an indie black and white adaptation of Shakespeare's Much Ado About Nothing, which was released in 2013. The filmmaker revealed that the producers even joked that he should make another Shakespeare adaptation over a 'long weekend,' in hopes of getting him in a better mood.

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"Let me tell you how bad things got for me. I was like, "I am not doing anything like that, I'm not even going to think of a limerick. Every time I think, 'Oh, I have time to create,' I'm gonna be like, 'OK, good. What's wrong with the movie? What do I need to work on? What ADR isn't finished? What do I need to think about? Let's write a memo about this? How can I get a better version of this? Just keep pushing.' And at some point, Kevin and Jeremy [Latcham] jokingly kind of said, 'Oh, it's a long weekend, are you sure you don't want to maybe make a Shakespeare movie?' That's how burnt I was. They were like begging me to make a Shakespeare movie because they were like, 'It makes him happy, he might calm down.' I'm still in that phase of like, 'But wait, I have notes!' I can't let go. I feel like, "Oh no, everybody's going to see my failure." But I am proud. I worked really hard. I'm proud of everybody in the movie, I'm proud of everyone who worked on the movie. ... This child may be insane, but it's mine. It's like Ultron. It may try to kill you all. But I love it."

It isn't known what movie Joss Whedon will make next, but it certainly won't be for Marvel, not in the next few years anyway. Do you think the filmmaker will eventually come back to Marvel Studios? Or do you think his time there is done?