Though Iron Man has plenty of flaws in the Marvel Cinematic Universe, the films failed to explore the character's true dark side. Tony Stark is popular in part because of his many weaknesses, and the MCU admittedly showcases his hubris, ego, and failure to work with others. Unfortunately, now that Iron Man is dead as of Avengers: Endgame, Marvel Studios can no longer depict the greatest stories that shows Tony at his weakest and most vulnerable: stories about his alcoholism.

In the MCU, Tony Stark is an egotistical, arrogant, womanizing, free-wheeling arms dealer with no real moral compass to speak of until he is kidnapped by terrorists working for the mysterious Ten Rings organization. Even after becoming Iron Man and attacking those who used his weapons to kill civilians, he still has much to learn; he disrespects his friends and colleagues, and in one memorable scene in Iron Man 2, engages his friend James Rhodes in a drunken powered-armor fight. But that pales in comparison to Tony's antics in the comics.

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In one of the most memorable stories in Iron Man's long history, Demon in a Bottle, written by David Michelinie and Bob Layton with art by John Romita Jr. and colors by Bob Sharen, chronicles Tony's long struggle with alcohol addiction. When Tony's Iron Man's armor suffers a catastrophic malfunction and accidentally kills an ambassador, he turns his armor over to the government, is forced to resign from the Avengers, and fights with his butler Jarvis (who leaves Tony's service). During this time, Stark's already-prominent drinking habit evolves into an addiction; he even flies into battle while drunk.

While the villain Justin Hammer is eventually revealed to have sabotaged the armor and fences are mended with Jarvis, Tony's drinking problem is unfortunately far from over. In the story Deliverance told in Iron Man #182, Tony has hit absolute rock bottom and wanders the city streets alone during a snowstorm; still addicted to drink, he even sells his coat for a bottle. In the midst of the storm, his homeless friend Gretl dies in childbirth, and Tony almost succumbs to the cold as well. After a stay in the hospital, Tony vows to give up the bottle for good, and - crucially - asks James Rhodes to help him kick his addiction. Eventually, Tony would regularly attend AA (Alcoholics Anonymous) meetings and even sponsor Carol Danvers, then going by Ms. Marvel.

Due to the nature of the mature subject matter, it was unlikely Disney would ever allow Demon in a Bottle to be adapted for the big screen. Tony engages in plenty of self-destructive behavior in the films (especially in Iron Man 2), but his drinking problem is notably never addressed. Iron Man is one of the most flawed superheroes ever put to film, but the MCU missed a massive opportunity to show Tony overcome a very real addiction that plagues many in the real world.

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