Stupidity: The security system is able to automatically ascertain the malfunction to the exact valve, and the electrical problem, but the alarm is not triggered at that point, but only when the holding cells are already filled with water and Breslin is making his return. They are on a ship, the fact that it's taking on water feels like a pretty important issue to monitor.
Stupidity: When Jonathan is chasing the truck to try and save Sarah, he could have removed his heavy backpack and run faster...but instead just leaves it on. No wonder he wasn't fast enough.
Stupidity: If the ninja can inhabit a dead body (and one that has been dead for a LONG time, even) without any penalty in his agility and powers and it is stated that only another ninja can truly kill him (which surely seems correct, since he would still fight even when hit by hundreds of bullets), the whole movie plot that involves him possessing Christie - who is a reluctant and part-time host - does not quite make sense.
Stupidity: The team raids the house and locates 5 people inside deemed to be Russian operatives. They are subdued and placed on their knees, while some of the team works on gathering intel from the home. The subjects should have been handcuffed/zip-tied. Since they were not they were able to grab stashed weapons and cause a gun fight which led to one of the entry team's members being killed and all the Russian operatives killed. It's common knowledge to restrain people. Cops and military always restrain. (00:04:00 - 00:12:00)
Stupidity: Patrick told Dwayne to get Cisneros to kill Zara, apparently because he believed Cisneros could get the job done. Cisneros went into Zara's house with his gun ready to shoot, but not before pinpointing Zara's location. He saw the refrigerator door open yet entered the room without looking left and right (behind the door); Zara was able to disarm him. Zara was also able to escape Cisneros' repeated crazy swings at her with a samurai sword. Zara fatally "sliced" his neck with a pizza cutter. (00:21:44 - 00:23:07)
Stupidity: Ben is standing behind Marley with a gun to her head as protection against Aaron, who is pointing a gun at him. Aaron shoots Marley and Ben just stands there, first looking at Marley on the ground then looking at Aaron (standing about ten feet away). Aaron screams and shoots Ben in the abdomen. After Ben falls, Aaron shoots three more rounds at him but misses. Ben is also able to stand and walk around despite his abdominal wound. (01:17:30 - 01:20:40)
Stupidity: The Joneses forget to change their New York license plates to Georgia ones as part of their cover.
Stupidity: During the gun battles with the "Tropic Thunder" actors, not one of the Flaming Dragon soldiers notice there is something strange about how the actors are firing their weapons (i.e, in the air, over the heads of the Flaming Dragons, etc.) or that there is no damage inflicted when the actors are shooting at or near objects in the area. Those two factors alone would tip off the Flaming Dragons that blanks were being used in the weapons of the actors.
Stupidity: After making love, Selina notices Batman's scars. She surely was caught in the moment, but, it's something she really was bound to notice sooner. (00:53:10)
Suggested correction: She notices the scars on his back first, which are the worst of those on his body, this may well be the first time she sees his back.
Stupidity: When Alice opens the door for the dumbwaiter, how did she not see the bottom of the elevator was removed when she was looking right at it? She even realised it was missing as she was getting in, but she still let go and fell to the basement.
Stupidity: As soon as Bundy got into the building (instead of when he was still outside), Kaminsky asked him for a "camera check." Bundy had a yellow button with a big star in the center pinned to his jacket's right lapel. Bundy put some fingers next to the button and raised his lapel with the others, making it obvious he was wearing a camera. When Manson got into the lobby (area likely to be under video surveillance), Reese (who saw Bundy and Manson outside) came into the building to give them weapons. (00:03:50)
Stupidity: This highly trained squad of soldiers is sent into a known contaminated zone with all manner of chaos going on within in...and the second one of them sees a woman outside his APC he ignores a direct order and pops outside to see how she's doing.
Stupidity: How would a devout catholic like Angela not believe in the devil, as she tells Constantine? Makes no sense.
Suggested correction: Some Christians don't believe in the literal personification of the Devil. They see him more as a metaphor for all human sins. So according to them, the Devil is not something to blame evil on. Everybody has God and the Devil in them.
Stupidity: Sam slid under the truck to narrowly escape the lioness. Even though there was more than enough ground clearance, the lioness did not go under the truck to attack Sam, as though the truck's frame were a barrier. The lioness could have easily crawled under the truck (unless a CGI lioness is not as spry or nimble as a "real" lioness). Sam being under the truck would not constitute adequate protection from an attacking lioness. (01:10:30 - 01:35:20)
Stupidity: The Analyst wishes to hide the true identity of Neo from anyone inside the Matrix, so his appearance is altered. But in this new Matrix Neo is also named Thomas Anderson, his name from before he was pulled from the Matrix originally, and he is a famous game developer that created a video game series called "The Matrix." It is frankly astounding that anyone actively looking for Thomas Anderson would not immediately see through this ruse and instead would be fooled by balding hair.
Stupidity: Becky possessed the mysterious key that the four neo-Nazi prison escapees were at the lake house to retrieve. Becky didn't know what the key was for, so did not have a vested interest in it. By first denying that she knew where the key was and later refusing to give it to Dominick, her father was killed. Had Becky simply handed over the key when Dominick asked for it, it is possible no-one would have been hurt/ killed. Becky keeping the key with no importance to her served to further the plot.