Continuity mistake: At the start as Ethan is handcuffed to the chair, the drop of blood underneath his nose constantly changes in size depending on the camera angle. This is also true when we cut back to that scene later in the film. (00:00:45)
Continuity mistake: In the scene in Berlin, the female member of the IMF team starts with no special glasses/goggles, then has them up on her head, then, just before the shooting begins, she puts them over her eyes, but later, while the shooting is still going on, they are back up on top of her head. Then they completely disappear. (00:17:50)
Continuity mistake: The red wine stain on Davian's shirt is much redder when he enters the restroom than just after the wine is spilt on him. (00:51:00 - 00:52:20)
Continuity mistake: During the bridge scene, soldiers approach the armoured vehicle to spray it with orange gel. As they approach, the vehicle has a triangular reflector on the rear side. In the shot five seconds later showing the orange gel being sprayed, the rear reflector is circular. (01:03:40)
Continuity mistake: In the bridge scene Ethan runs to the IMF truck to retrieve the G36 gun case. He shoves it out across the ground and flees to escape the approaching missile. When the missile strikes, the explosion knocks Ethan against a car, and the gun case is blown further across the ground and appears to come to rest right next to him; yet in the next shot he has to run several steps to get to it. (01:07:00)
Continuity mistake: When Ethan is running through the Shanghai streets, he passes a man holding a vase. In the immediately following wide angle the man has vanished.
Continuity mistake: When the sewer lid is removed, it is pushed to the right (compared to the location of the car) but when it is pulled back, it lies behind the hole (again compared to the location of the car).
Continuity mistake: Towards the end of the film, after Tom has been electrocuted to destroy the bomb implanted into his skull, we see the female lead trying to restart his heart, each time they show his eyes, they are closed or open in different shots, and if they are closed, you can see his eyeball moving underneath the eyelid.
Continuity mistake: When Ethan and the team are being attacked on the bridge, Ethan's back left jean pocket is ripped. However, when Ethan is recovering from almost falling off of the bridge, his pocket is intact.
Continuity mistake: When in the Vatican, by the DHL truck, Declan's fringe keeps changing in each angle.
Continuity mistake: When Ethan Hunt has replaced Damion's character, in the bathroom, the white handkerchief in his hand disappears and reappears in sequential shots, as he points two fingers to his bodyguard.
Continuity mistake: After the fight on the bridge Ethan drives away in the Mercedes. But the road was blocked by the yellow truck. And if the Mercedes had been in front of the yellow truck in the first place, its driver would probably have driven away instead of leaving his car.
Continuity mistake: Near the end of the movie, when Tom Cruise is running through the narrow streets in China, while on the phone with the guy from IMF, he is nearly struck by a truck coming very quickly from an adjacent street. In the next shot, they show the road from which the truck had just come. The thing is, it's filled with people, none looking like a large truck just went barreling by. The truck was going at too high a rate of speed to have come from the heavily populated street.
Continuity mistake: When Ethan - after getting the rabbit's foot - calls Musgrave, his location is shown on a map. He is in the northern part of Shanghai, quite some distance from Pudong, the area south of the river, where the high rise buildings are. However in the next clip, he drives down the on-ramp to The Bund, which is the street right next to the river, opposite Pudong. So he's been driving in circles - and extremely fast.
Continuity mistake: When Davian and Hunt are fighting in front of Julia, Davian slugs Hunt on the floor and walks for the gun. Hunt is twice seen lying on a floor with no glass, the second shot a close-up showing his face and clean arm. In the next shot, as Hunt rallies and goes to rise from the same body position, he's lying in piles of glass and has glass stuck to his arm.
Continuity mistake: When Ethan is offered the task and refuses, he is told that just in case he has a change of heart, that the team will be "wheels up at sunrise". When he arrives the next day, the sun is much more in the position of late morning.
Continuity mistake: When the IMF team, plus a few more for protection, are in a helicopter, the protection team, two of them, plus Ethan, are hanging outside the helicopter, all strapped in, of course, but, suddenly, the door is closed and everyone is inside.
Answer: It's never explained. This is what's known in the film industry as a McGuffin, a term popularised by Alfred Hitchcock, which is an item that's crucial to the plot, but the exact nature of which is never revealed because it actually doesn't matter in the slightest.
Tailkinker ★