- Alternate Character Interpretation: When The Fog tips off the Russian cops about Ethan, was he double-crossing Ethan, or had Ethan asked him to do that in order to get the Russian in the area to witness their heroism and fully clear his name.
- And You Thought It Would Fail: Mission: Impossible III had performed below expectations at the box office, as well as Tom Cruise's last few films, and many prognosticators were surprised the studio had approved a fourth film. Box office analysts thought it was a bad move for Paramount to schedule the film for Christmas weekend, already crowded with other releases, and a season that wasn't known for being fertile ground for action films. Strong word of mouth, with many calling it the best film of the series, propelled it to strong box office, becoming one of the highest-grossing films of the year and easily leading Christmas weekend.
- Big-Lipped Alligator Moment: Hendricks impersonating his own dragon for one scene doesn't really move the plot forward in any significant way, and his reason for doing so is never explained.
- Even Better Sequel: This was easily the best-reviewed film of the series at the time, with 93% on Rotten Tomatoes; III, the previously-best-reviewed, only managed a 71%. Cinema Wins even sums up his review with, "So apparently, no one told Tom Cruise or Brad Bird or J. J. Abrams that this was a 4th movie in a franchise and it's supposed to suck."
- Growing the Beard: This film is what took the franchise from "popular, but critically divisive" to "one of the most critically acclaimed film franchises of the decade".
- Harsher in Hindsight:
- The trailer for the film shows the bombing of the Kremlin, a major symbol of the Russian government. The trailer was played on the same day as the terrorist attacks in Oslo, Norway.
- Ethan breaking his ankle during his fight with Cobalt, after Tom Cruise actually broke his ankle during the filming of Rogue Nation.
- Hilarious in Hindsight:
- Word of God says William Brandt was put in the movie so that he could become the series' new protagonist if Tom Cruise ever left. In the end, Cruise stayed as the lead... but around the same time, Jeremy Renner did end up becoming The Bourne Series' new protagonist after Matt Damon dropped out of The Bourne Legacy.
- Josh Holloway's brief role in the botched operation that starts the film has him using Augmented Reality contact lenses to pinpoint a target-something that his character on Intelligence (2014) has as a superpower.
- When Ethan first meets Jane, she introduces herself as "Agent Carter." Even funnier as Agent Carter's actress, Hayley Atwell would later sign up for Mission Impossible 7+8.
- Léa Seydoux, who plays a cold Professional Killer with a personality not too different from a James Bond villain in this film, ends up playing Bond's love interest in Spectre and No Time to Die.
- In The Incredibles, Brad Bird spoofed this franchise's staple of self-destructing message sent by a secret agency. Years later, he would direct this movie, which is a part of said franchise he spoofed.
- Magnificent Bastard: Kurt "Cobalt" Hendricks is a former specialist in nuclear endgame theory, who grew weary of treating the lives of millions like a game, and came to the conclusion that nuclear war is an inevitability. Hijacking the IMF's operation at the Kremlin, Hendricks frames the agency for bombing the landmark, raising tensions between Russia and the U.S. He forces a nuclear physicist to verify launch codes by kidnapping his family, then releases the family and kills the man to cover his tracks. Hendricks launches a missile at San Francisco in order to start a war so the survivors will declare a worldwide armistice. When Ethan Hunt comes close to stopping the missile, Hendricks leaps to his death attempting to ensure his plan succeeds, coming within a second of accomplishing his goals. Despite his destructive goal, Hendricks genuinely believes that Utopia Justifies the Means, and manages to play the IMF and the world's governments for fools all the while.
- Moral Event Horizon: Hendricks crosses it by committing suicide to ensure his Evil Plan succeeds. This shows just how far off the slippery slope (and it's a very slippery one, indeed) he's jumped and that he values his plan more than his own life.
- Signature Scene: Ethan climbing the Burj Khalifa.
- Win Back the Crowd: The movie got more love from fans of the original show because it wasn't strictly "Ethan Hunt and his friends" but that each team member was fully developed in their own right. There is also significantly less gunplay, with more emphasis on trying to get in and out without anyone knowing what happened.
YMMV / Mission: Impossible – Ghost Protocol