Thor looking surprised and delighted in Thor: Ragnarok

When the Marvel Cinematic Universe kicked off with "Iron Man" in 2008, few would have predicted that two decades later it would still be going strong. With dozens of movies, plus an ever-expanding roster of TV shows taking us even deeper into the lives of the franchise’s various characters, the MCU has reached the point where it has arguably eclipsed any other franchise in terms of size, scope and fanbase.

Yet, somehow the Universe keeps expanding with new characters, new story elements, and new ideas. So, even as fans have become intimately familiar with so many residents of the MCU, its latest movies and TV shows still manage to keep them guessing, whether they’re building on revered comic-book storylines, baking in perfectly considered moments of fan service, or finding ways to make viewers fall in love with favorite superheroes all over again.

From "Iron Man" through "Spider-Man: No Way Home" and beyond, filmmakers continue to keep viewers off-guard; it is an undeniable ingredient in the thrill of being an MCU fan. With that in mind, here are the most unexpected things to happen in the MCU thus far.

The Mandarin reveal in Iron Man 3

A surprised Trevor Slattery puts his hands up

The big reveal of "Iron Man 3" that the Mandarin’s true identity was not who it appeared to be became a polarizing moment in MCU history. Love it or hate it, the Shane Black-engineered moment was one most viewers did not see coming – and nearly a decade later, would become a major plot point in a different MCU film.

When trailers were initially released for the third film in the "Iron Man" series, fans learned the Mandarin would be joining the franchise; a longtime comic book adversary for Iron Man, his appearance felt as inevitable as it was straightforward. Yet, Mandarin had a slippery history when it came to his racial origins in old comic books, and the casting of Oscar winner Sir Ben Kingsley seemed to indicate (for some) a possible whitewashing of the character that might just make matters worse.

Ultimately, Robert Downey Jr.’s Tony Stark discovered the supposed leader of the Ten Rings was an actor named Trevor Slattery, hired to terrorize Stark in the guise of the Mandarin. A self-centered coward who saw the Mandarin as "just a role," he was a smokesecreen for Aldrich Killian (Guy Pearce), the ultimate mastermind behind this particular Mandarin terrorist threat.

While fans were torn about this re-imagining of Iron Man’s arch-nemesis, many enjoyed Slattery’s antics, and a Marvel One-Shot short depicting his life in prison (and subsequent abduction by the "real" Mandarin) was well-received. Consequently, Marvel surprised fans once again a decade later — by making Kingsley’s Slattery a significant supporting character in 2021’s "Shang-Chi and the Legend of the Ten Rings," continuing his storyline as a prisoner of the title character’s father, the real Mandarin.

Kingpin in control of his business enters into the MCU
Quicksilver looking surprised after getting hit saving Hawkeye in Age of Ultron
Quill gleefully dances in front of Ronan in Guardians of the Galaxy
Aunt May looks serious in Spider-Man: No Way Home