Ironman series and avengers
The script was not completely prepared when filming began, since the filmmakers were more focused on the story and the action, so the dialogue was mostly ad-libbed throughout filming;
Jon Favreau acknowledged this made the film feel more natural. Some scenes were shot with two cameras to capture lines improvised on the spot;
Robert Downey Jr. would ask for many takes of one scene since he wanted to try something new.
Gwyneth Paltrow, on the other hand, had a difficult time trying to match Downey with a suitable line, as she never knew what he would say.
400 extras were meant to be filmed standing at Tony Stark's press conference, but
Robert Downey Jr. suggested they ought to sit down, as that would be more realistic and comfortable. To avoid spoilers about the final press conference, the extras were told that it was a dream sequence.
Jon Favreau wanted
Robert Downey Jr. because he felt the actor's past was right for the part. He commented: "The best and worst moments of Robert's life have been in the public eye. He had to find an inner balance to overcome obstacles that went far beyond his career. That's Tony Stark. Robert brings a depth that goes beyond a comic book character having trouble in high school, or can't get the girl." Favreau also felt Downey could make Stark "a likable a$$hole", but also depict an authentic emotional journey once he won over the audience.
The montage of Tony Stark's life story was created by editor
Kyle Cooper, and contains real-life photos of a young
Robert Downey Jr. and his father
Robert Downey Sr..
Ghostface Killah, a long-time fan of the Iron Man comics (he uses the aliases "Ironman" and "Tony Starks", titled his 1996 album "Ironman" and samples clips of
Iron Man (1966)), got a cameo as a Dubai tyc00n. However, his scene was cut from the final film.
Jon Favreau apologized to Ghostface and used his "We Celebrate" video in the film.
A lot of Whiplash's identifying features were suggested by
Mickey Rourke himself. He wanted to perform half of his role in Russian, and consulted on the character's tattoos and gold teeth as well as having a pet cockatoo. In fact, Rourke paid for the bird and the gold teeth out of his own pocket.
The DJ at Tony's birthday party is DJ-AM who died after principal photography had wrapped, making this his last film project. During the end credits, the film is dedicated to him.
The rooftop where Tony and Pepper kiss at the end of the movie is located on an apartment building overlooking Flushing Meadows where
Jon Favreau lived as a child.
'Robert Downey, Jr.' kept food hidden all over the lab set and apparently nobody could find where it was, so they just let him continue doing it. In the movie, that's his actual food he's offering and when he was eating, it wasn't scripted. He was just hungry.
The final end credit scene was added after
Robert Downey Jr.. encouraged a scene rewrite: after Tony Stark falls back to Earth, he originally awakens and asks, "What's next?". Robert Downey Jr. thought the line could be more interesting, and the idea of going to a local shawarma restaurant was born. The scene was added one day after the global premiere. Since then, shawarma sales in Los Angeles, St. Louis, and Boston have reportedly skyrocketed.
In the final end credit scene, Captain America is the only one not eating. That is because
Chris Evans got a buzz cut and grew out his beard after The Avengers was done filming. He was called in later to do this extra scene and refused to shave off his beard due to having been filming
Snowpiercer (2013) at the time, so they gave him the prosthetic jaw. He holds his hand over his face because the prosthetic made him look like he'd been attacked by a hive of angry bees. He also is unable to eat or talk with the prosthetic on. The wig he wears as Captain America is also quite clearly visible in certain shots of this scene.
Thor is knocked off screen three times: once by Iron Man and twice by Hulk.
The shocked expression of Loki after being slammed by Hulk was created by animation director
Marc Chu shaking Hiddleston violently and repeatedly.
The Post-credit scene at the end of Iron Man 3 with Bruce Banner was Robery Downey Jr's idea
she admitted to sleeping with alot of people due to her being raped as a teen
Maybe that was the look in the 80s though 
