Joss Whedon Originally Wanted Zooey Deschanel to Play the Wasp in The Avengers
The Marvel Cinematic Universe didn't introduce the Wasp until 2015, when Evangeline Lilly portrayed the character alongside Paul Rudd in Ant-Man. While the plans for Wasp in the MCU seem pretty substantial going forward, there were actually plans for the founding Avenger to appear a few years earlier than she did. Joss Whedon wrote a version of Marvel's The Avengers that featured Wasp as a major character, and he wanted the role to go to New Girl star Zooey Deschanel.
The Story of Marvel Studios: The Making of the Marvel Cinematic Universe is a new book from Tara Bennett and Paul Terry that details the behind-the-scenes creation of the MCU. In the section about the groundbreaking Avengers movie in 2012, the book reveals that there was an iteration of the movie that focused on Wasp as a main character and featured Zeke Stane, Obidiah's son, as the main villain.
Heading into production, there was concern that Scarlett Johansson wouldn't be available to reprise her role as Black Widow after appearing in Iron Man 2. Whedon ended up rewriting the script to remove Black Widow and introduce Wasp, though Hope Van Dyne ended up becoming the focal point of the entire story.
"It was all about The Wasp," said producer Jeremy Latcham. "He wanted to cast Zooey Deschanel. [Wasp] was the funniest character in the whole movie, and well-written."
According to Whedon, who is quoted in the book, he actually went a little too far with his Wasp tale. She became the main character, which led to an issue when Johansson's conflicts were resolved. The entire Wasp storyline was ultimately scrapped.
"The Wasp happened because there was a short period where it looked like we weren't going to be able to get Scarlett [due to scheduling conflicts], so I was panicking," Whedon said. "I thought, 'Hold on, we could do The Wasp.' Then I fell in love with that. But we did get Scarlett, and then I realized I had written this entire movie about The Wasp. Oops. I overcompensated there."
Most Marvel fans would probably agree that the Wasp we ended up getting in the MCU was definitely worth the wait, and it didn't come at the expense of Black Widow. If Johansson had been just a little bit busier we'd be experiencing a very different MCU right now.