The entire movie is the mole hunt.A very elaborate one. Kittridge suspects Phelps from the beginning. Ethan is sent into uncover the mole. The murders of the team were not expected, but prepared for by having the second IMF team around in case something happened. The scene in the restaurant, the arrest of Ethan's parents, and the CIA invasion were staged to make Phelps think they were off his trail. Ethan was genuinely surprised by Claire at the beginning. The fact that she survived causes him to think she is in league with Jim, though he wants to not believe this. We see later that, as soon as he sees Jim and listens to him accuse Kittridge, he instead envisions Jim as the villain. He even suspects Claire for a moment. Kittridge does not seem surprised upon seeing Phelps alive, even though Ethan never said anything to prepare him for this.
- Consider how during the scene at the aquarium restaurant, nobody in the room makes any effort to notice or prevent Ethan from unwrapping his explosive gum. It seems out of character for IMF agents to have this lack of observation skill, but it's unlikely they'd let him pull this sleight of hand if they really were trying to apprehend a mole. The exploding gum is shown later in the film to be survivable so the waiter who was Blown Across the Room probably survived. Oddly, nobody even slightly attempts to chase after Ethan after he ruptures the aquarium and flees the water flooding the place.
John Voight's Jim Phelps is not the real Phelps.He's a rogue SYNDICATE agent that killed the real Jim (Peter Graves) and took his place. He decided that both the masquerade and his loyalty to the SYNDICATE are through, so he decides to be a mole for hire.
- Alternatively, he could be an IMF agent who was brought in to take on the role of the 'original' Jim Phelps after the real one retired (much like some fan theories that the different James Bond actors represent different agents who are given the same name and agent number to increase Bond's reputation).
- There's actually a fanfic based on this very premise- "The Oldest Trick in the Book"- where Ethan is visited by Cinnamon Carter at the funeral of the 'fake' Jim Phelps and learns the man's real history; the fic even concludes with the real Jim acknowledging Ethan as the future of the agency.
The Rabbit's Foot is the Luck Virus.The MI movies take place in the Red Dwarf universe. The Rabbit's Foot in MI:3 is a prototype Luck Virus. Untested. Dangerous stuff. Ethan Hunt is probably infected already. The virus may even be collected from the cells of top MI agents.
The real mole in the first movie was Dan BriggsBriggs saved the world more times in one year than James Bond does in a good decade, and how did the IMF repay him? They took his team away and gave it to Jim Phelps. What's more, his teammates never so much as spoke of him ever again. The first movie was his plot to destroy the IMF in general and Phelps in particular.
- Adding to this, Dan Briggs either killed or abducted the real Jim Phelps and took his place through plastic surgery etc (all of the old guard like Cinnamon, Rollin etc are long gone, so the newer agents wouldn't know the difference).
This takes place in the same verse as The Pied Piper of Hamelin.The Svardians are descended from the children of Hamelin and of an English town; that's why the language is the way it is.
Jon Voight's Jim Phelps is really the son of Peter Graves' Jim Phelps, James Phelps Jr.Given Voight looks middle aged in contrast to Graves around the time being a senior and how Voight during in his acting was around his twenties and too young to serve in the Korean War which Graves' Phelps has. There could be a lot more to the film's Phelps choosing to betray the IMF and of why he was disillusioned. Voight's Phelps Junior could be The Vietnam Vet during the timeframe of the television when his father the Jim Phelps portrayed by Graves was doing missions, initially a "Well Done, Son" Guy wanting to follow his footsteps of his father by first serving in Vietnam just like how Graves' Phelps started out by serving in Korea prior to joining the IMF. However, unlike Graves' Phelps who kept his idealism and patriotism throughout the series, Voight's Phelps may have being planted with cynicism upon seeing unmentionable War Is Hell horrors committed by both sides and eventually how the conflict itself resulted in America losing the war and Voight's character being seen and treated as a figure of hate for his service to begin with, turned him into a Shell-Shocked Veteran who would gradually undergo Sanity Slippage that would eventually serve as the true catalyst for his villainy in the first film. Voight's Phelps would join the IMF as a means to exorcise his traumatic demons by living up to his father and upholding operations elsewhere outside of Graves' Phelps' missions shown in episodes of both the original and the 1988 series, but likely developed a Inferiority Superiority Complex for being in the shadow of Graves' Phelps and may have started to resent the IMF for favoring his father over him even during service. It's only after feeling disillusioned with his efforts it has exacerbated his cynical 'Nam-dated mindset, his insecurity of his inability to truly measure up to his legendary father and warped traumatized mentality he goes totally insane and pulls a FaceHeel Turn as "Job," becoming an Evil Counterpart to Graves' Phelps and an Antagonistic Offspring determined to destroyed his own father's legacy out of blaming his celebrated experience and unwittingly putting him permanently under his shadow for make him feel worthless that exacerbated his choice to go bad as a means to escape Graves' Phelps' shadow.
- Interesting theory but unlikely. The Season 5 episode "Homecoming" establishes that there's a guy in Jim's hometown who was the only survivor of his unit in Vietnam, meaning Phelps would have to already have a son aged around 18 or so during the time period of the TV series.
Jim killed Ethan's dad
- In the movie, Jim fakes his own death and makes it look like Ethan is the mole. Coincidentally, Ethan's family has money problems because his dad died slowly and went through a lot of medical bills. This makes Ethan look like the mole, because it gives him a financial incentive to betray his country. But what if it's not a coincidence? Maybe Jim poisoned Ethan's dad as part of his long-term plan to pin the blame on Ethan.