Mr Fantastic was to make his MCU debut years ago in a deleted scene
Reed Richards aka Mr Fantastic was supposed to be introduced to the MCU in the first Doctor Strange film back in 2016.
Mr Fantastic had already been played by two actors on film before John Krasinski’s MCU cameo--Ioan Gruffudd and Miles Teller. In a recent interview, screenwriter Michael Waldron, who wrote both Doctor Strange films, said he had initially planned to introduce the character in the first instalment back in 2016.
In an interview with Empire, Michael said he had written a post-credits scene for Doctor Strange, which introduced Reed and his headquarters--the Baxter Building. "In my very first draft, I wrote a tag just for the hell of it, of the events of the movie being recorded and reviewed by somebody in the Baxter Building, and a stretchy hand coming into frame to run it back. Reed is probably my favourite Marvel Comics character, so I was always gunning to get him in here somewhere,” he said.
The rights of the Fantastic Four characters were with Fox and not Marvel, which is why the characters were not in the MCU. That is probably what stopped the character from appearing in the first Doctor Strange. That changed in 2017 when Marvel’s parent company Disney acquired Fox, which is what made John’s cameo possible.
Now, Marvel Studios is developing a Fantastic Four film but no details about the cast have been revealed. It is unclear if John will reprise his role there or if a new actor will be cast. The film, which will be directed by Jon Watts, is scheduled to be released on November 8, 2024.