Continuity mistake: When Obi-Wan falls off the walkway during the duel with Darth Maul, his lightsaber lands on a lit strip of the floor. A few shots later he jumps up and retrieves his saber, which is now resting on a dark area on the floor. Even if the saber continued to roll on the floor between the shots, it couldn't have ended up in this position. (01:50:50)
Continuity mistake: When the three Droidekas appear and attack Padmé's group, in the background you can see that Darth Maul has already ignited his lightsaber. After Anakin says "We gotta do something, R2", the Sith ignites his lightsaber again. (01:50:53)
Continuity mistake: After Darth Maul falls off the walkway, Qui-Gon jumps down after him, and there are several vertical beams behind them. In the next shot, they have suddenly moved past them, but in the following shot, they are fighting in front of the beams again. (01:51:05)
Continuity mistake: When Obi-Wan, Qui-Gon, and Darth Maul get cut off from each other in the corridor and Qui-Gon kneels down, Obi-Wan is standing in the background with his lightsaber pointed downwards. In the next shot, it's pointing upwards. (01:51:45)
Continuity mistake: As Obi-Wan is looking up at Darth Maul and Qui-Gon, they are fighting in the middle of the walkway. When Obi-Wan jumps up, they are at the doorway at the end of the walkway. They couldn't have reached the end of the walkway that quickly. (01:51:50)
Continuity mistake: When Amidala and some other guards use the ascension guns from the palace windows seven of them go up, when they are running along the corridor after coming off the window-ledge, there are about 13 or 14 of them. Then finally when they are surrounded by the droids, there are about 10 or 11 of them and Captain Panaka is not there. (01:53:30)
Continuity mistake: When Qui-Gon dies, you see him fall down - his hands clearly hit the ground and rest there after sliding off his body. In the close-up shot, Qui-Gon's right hand does not and rests on his stomach. (01:55:00)
Continuity mistake: When Qui Gon is killed, he falls to the floor with his right arm on the floor. The next shot shows his left arm falling and his right arm on his chest. (01:55:05)
Continuity mistake: Just before Obi-Wan jumps up from the pit, there's a shot of Qui-Gon. His lightsaber, which was lying on his left side after he was stabbed by Darth Maul, is now lying below his feet. (01:55:10 - 01:59:00)
Continuity mistake: Qui-Gon, Obi-Wan, and Maul are fighting in one of the bridges in the reactor room. In the next shot, when Maul kicks Obi-Wan, the three are now fighting next to a reactor. (01:55:28)
Continuity mistake: Qui-Gon kicks off Darth Maul with his lightsaber ignited. In the next shot, when he jumps to fight the Sith, the lightsaber is turned off, even though the turning off sound is never heard. (01:55:45)
Continuity mistake: Before the pod race begins, as Jabba the Hutt says, "Welcome.", the woman to his right has her hand on the wall. In the next shot, she is no longer touching the wall and her head is turned in a different direction. (01:56:00)
Continuity mistake: In the chamber room near the end of the movie, after the Queen throws the guns to everyone and goes to address the Viceroy, she starts to walk away from her chair. While she is doing that, you can distinctly see her lose her footing and slip on the floor. In the next edit she repeats this movement without slipping. (01:56:10)
Continuity mistake: When the final duel between Obi-Wan and Darth Maul begins, they are fighting in a particular area next to the pit. But when Obi-Wan cuts Maul's lightsaber in half, the background changes and they are suddenly fighting on a different side of the pit. (01:56:40)
Continuity mistake: At the end, after Darth Maul has knocked Obi-Wan into the pit, Obi-Wan is beginning to remember about Qui-Gon's lightsaber. The scene shows Darth Maul with the lightsaber in his right hand. When Obi-Wan leaps out of the pit and flies over Darth Maul, the lightsaber switches to Maul's left hand. (01:58:55)
Continuity mistake: When Obi-Wan kills Darth Maul, he grabs Qui-Gon's lightsaber with his left hand. But when he twists above Maul's head, he's holding it in his right hand. In the next shot, it's back in his left hand. (01:59:10)
Continuity mistake: When Darth Maul is killed and begins to fall, he is holding his lightsaber, but when we see him falling down the pit, no lightsaber is falling through the air. (01:59:15)
Continuity mistake: When Anakin and Obi-Wan walk up to greet Palpatine on Naboo, in the wideshot, a Republic guard is passing by them. In the close-up, the guard is gone. (02:00:40)
Continuity mistake: After the race, Anakin's face is dirty. When his mother kisses him, his face cleans itself between shots.
Continuity mistake: After Qui-Gon is struck by Darth Maul's lightsaber, he drops down, and his lightsaber is lying on the floor. In the shot where Maul turns around to face Obi-Wan, the sabre is not lying in the same place as before (seen from the colours of the floor), and the activation button faces upwards, which it didn't do in the previous shot. In the next shot of Qui-Gon, his lightsaber is now closer to him than in the previous shot.
Chosen answer: According to "Inside the Worlds of Star Wars: Episode I" by Kristin Lund, they are "laser doors which lock into position in response to potentially lethal power outputs that occur intermittently during plasma activation process" (the fight takes place in a plasma energy processing plant). There are six laser doors in deference to an ancient Naboo legend in which Chaos is held back by six inpentrable gates. As you say though, they're really just a plot device to add dramatic tension to the duel!
Sierra1 ★