"Avengers: Age of Ultron" is coming off of the second-best weekend in box office history, and the man behind the film -- writer/director Joss Whedon -- is opening up about some of the struggles he faced while making the massive follow-up to his 2012 Marvel debut. In an interview on the Empire Film Podcast (via The Hollywood Reporter), the director went into detail about how he clashed with Marvel Studios over the film. According to Whedon, the main point of contention between the filmmaker and the studio seemed to center around one scene that Whedon really wanted and one storyline Marvel fought to include. Spoilers ahead for those who haven't seen "Age of Ultron" yet.

According to Whedon, Marvel was not fond of the act two breather wherein the team takes refuge at Hawkeye's farm; on the other hand, the studio was "quite adamant" about adding in the scenes wherein Thor and Dr. Selvig visit a mystical Norse cave pool.

"The dreams [brought to life by Scarlet Witch's powers] were not an executive favorite either -- the dreams, the farmhouse, these were things I fought to keep," Whedon said. "With the cave, it really turned into: they pointed a gun at the farm's head and said, 'Give us the cave, or we'll take out the farm,' -- in a civilized way. I respect these guys, they're artists, but that's when it got really, really unpleasant."

When viewed in larger context of the Marvel Cinematic Universe, the cave sequence ties "Age of Ultron" to the rest of the mythology since it reveals the existence and importance of the Infinity Stones to Thor, and eventually the Avengers. Whedon also revealed that additional footage was shot at the cave, but the scenes were removed after they tested poorly with audiences.

The director also revealed that he wanted to put both Captain Marvel and Spider-Man in the movie, but Carol Danvers had not been cast, and Marvel's deal with Sony to share the wall-crawler was not finalized in time. "I would have put both of them [in Ultron], but neither of the deals were made."

This interview comes to light after Whedon pulled the plug on his Twitter account. The director left the social media site at some point on Monday, giving no concrete reason for his departure. Many have speculated that it may be in part because of nasty messages directed his way over plot points in "Avengers: Age of Ultron," but it's just as possible that Whedon had grown weary of the platform. He's spoken out about his dislike of Twitter in the past, particularly in a 2013 interview with Entertainment Weekly.

"I joined six months ago to specifically try to drive business to 'Much Ado About Nothing' because I figured 'Much Ado' needs all the help it can get," Whedon said in 2013. "The moment I joined, oh my God, what a responsibility, this is enormous work -- very fun, but it really started to take up a huge amount of my head space. I'm making a movie, I got a responsibility, this job doesn't pay very well. It's a fascinating medium, it's a fascinating social phenomenon. People are like, 'It's like a drug.' Yeah, and it's like a job. It's just another art form. Until I have a script I truly believe in or a tweet that's really remarkable, I can just walk away and get back to the storytelling I need to do."