Continuity mistake: When the Protagonist walks into Sator's office, a doctor is shown checking his blood pressure and is then ordered to leave. In one shot, the doctor is shown walking past the Protagonist, but in the next shot, the doctor is shown walking past the Protagonist a second time. (01:00:40)
Continuity mistake: Whilst the Protagonist, Sator and Kat are riding in Sator's yacht, Sator asks the Protagonist "What do you know about opera", and the Protagonist is shown facing forwards. The Protagonist then answers Sator's question and he suddenly has his head turned 180° to face Sator. (00:57:23)
Continuity mistake: When the Protagonist and Neil are standing in the hallway after averting the halide gas, Neil says "There's someone in here with us", and is shown standing right next to a wall when he says this. In the next shot, he is suddenly standing next to a bend in the wall. (00:44:05)
Continuity mistake: When Kat is talking with her son outside the school, just as she says "We will. We'll go together", a schoolgirl and her mother are shown walking past Kat, on her left. It then cuts to a closer angle of Kat and the mother and daughter have suddenly disappeared. (00:33:40)
Continuity mistake: When Barbara asks the Protagonist which bullet is which, when Barbara "picks up" the backwards gun, the bullet is fallen over on the table, indicating it's been dropped. (00:14:31)
Revealing mistake: In the temporal pincer soldier scene, the red team is shown moving forward in time, jogging slowly, with a reverse explosion in the background. However, there is one red soldier in the foreground running in reverse, which is inconsistent. (02:02:35)
Continuity mistake: When the Protagonist and Neil first meet in the hotel, just after Neil puts his hand out to be shaken, the Protagonist begins to reach out his hand for the two to have a handshake. In one shot, the Protagonist is sitting back in his chair, but when the two shake hands in the next shot, he is suddenly leaning forwards, then in the next shot after that, he is suddenly sitting with his back against the chair. (00:18:26)
Continuity mistake: When Neil first sits down next to the Protagonist, he is looking forwards whilst he starts talking, but when the shot cuts, he is suddenly looking at the Protagonist. (00:18:18)
Continuity mistake: Just after the siege in the opera house has begun, the scene cuts back to the truck with the SWAT team inside. The driver is shown with his head turned to the right to face the man in the passenger seat while he says "Wake up the Americans." The camera then changes angles and the driver is suddenly looking forwards out of the front window. (00:01:25)
Continuity mistake: At the start of the scene where the Protagonist is having dinner with Kat in the restaurant, there is a shot from behind him where he says "Traced it back to Arepo", and he is shown clasping his hands. It then cuts to a shot from in front of him where his hands are now placed on the table. (00:28:20)
Continuity mistake: When the Protagonist has Sanjay held at gunpoint, he says to Priya that if Tenet is important to her then she can tell him, to which Priya replies not while he has a gun pointed at her husband's head. The Protagonist then pulls the gun away from Sanjay's head and begins to step back. It then cuts to a shot focusing on Priya, and the Protagonist, shown standing on the left corner of shot, is suddenly standing completely still and motionless. (00:22:20)
Audio problem: Just after Neil tells the Protagonist that he never drinks on the job, there is a shot focusing on the Protagonist where he says to Neil that he's well-informed. In the corner of shot, just after the Protagonist finishes his line, Neil is heard saying "Well", but his lips are not shown moving. (00:18:58)
Continuity mistake: When the Protagonist is on the phone with the contact in Mumbai, just as he says "We live in a twilight world", two men are walking past him. One man is wearing pink robes and the other is wearing a black and red checkered shirt. A closer shot of the Protagonist is then shown, where the two men are shown walking past him a second time. (00:17:45)
Continuity mistake: Just after the Protagonist has had some of his teeth pulled out by the Russian driver, the driver begins turning the time on a clock back by one hour. He is shown holding the clock with his right hand, and is shown turning the time back with his left hand. But in the next shot, he is suddenly holding the clock in his left hand and his right hand is at his side. (00:08:10)
Continuity mistake: When the Protagonist is on the boat and is talking with the agent, just after the agent first mentions Tenet, he says "It'll open the right doors, but some of the wrong ones, too." Whilst he says this, the Protagonist is shown looking straight forwards out to sea, but when the camera changes angles, he is suddenly looking at the agent. (00:10:40)
Continuity mistake: When the Protagonist is being questioned on the train tracks by the Russians, the driver removes a cyanide capsule that the Protagonist had hidden in his uniform. In one angle, he is shown holding the capsule with two fingers and one thumb around the bottom half of it. When the shot cuts to a different angle, he suddenly has one finger positioned on top of the capsule. (00:07:23)
Continuity mistake: When the soldier explains how the red and blue teams are going to attack, he paints red and blue lines on the screen. Check the arrow on the blue line: it changes style between shots. (01:57:57)
Visible crew/equipment: When the protagonist inverts himself and gets in the car, a shot from outside reveals a small black car behind him reflected on the bumper. From the immediate wide angle the car is gone. Seemingly, the filming vehicle. According to footage from the making-of, a small black car was the one holding the filming crane. (01:32:00)
Continuity mistake: When Andrei is about to beat Kat with a belt, he throws cushions at her. One lands right next to her head, but disappears a shot later. (01:03:45)
Continuity mistake: When the protagonist has dinner with Kat the glass in her hand appears/disappears randomly between shots. Also, the position of her hands is not continuous when the scene starts. (00:28:50)
