Stupidity: The protagonist with her kid stops a car with two guys, in the middle of the night in an isolated country road. Both the adult and the kid scream that a dangerous maniac is chasing them. So naturally, the two guys (who do believe them, it's not that they are being dismissive) offer them some hot coffee, and they drink it right there in the middle of the street, not dialling for help, getting in the car to drive away or anything, because that's what normal people do when you tell them a serial killer is nearby; stop for a hot cuppa.
Stupidity: Diana and Rita call each other on the phone when the killer is approaching, but neither calls the police. Rita might have been pressed for time because the killer's van was chasing her car (even if she'd had time, looking at the scene), but Diana definitely could have spared a few seconds after Rita hanged up, the killer was literally miles away.
Stupidity: A significant plot point at the beginning of the movie is based on the fact that the killer changed the color of the van from black to white and was untraceable. In the rest of the movie, everyone knows that the van is white, he is constantly identified solely because of that, almost to the point of being comical (there are plenty of white vans around, just like there were plenty of black ones.), and yet he never ever changes color again even with days to spare. This sudden change of M.O. is never explained nor brought up.
Stupidity: The doctor speaks to Diana in the hospital room. The scene is played like Diana just woke up and just discovered about her status, which they discuss with the medical explanation for it. She reaches out with her arms feeling up blindly (literally, of course). The first thing she does as the doctor leaves, is to put the titular black sunglasses on. She shouldn't even know they are there - and why should they be, after all. (00:18:15)
Stupidity: The police inspector leaves her calling card, not written in Braille, to the blind protagonist, asking her to call her in the next hours if she finds something out. She knows she lives alone. The scene is played unironically.
Suggested correction: There are devices that blind people use to read print to them, so they don't have to rely on everything being in Braille.
I am sure, but they show the 'training' she receives from Asia Argento in the couple of previous days, the only device being a phone that accepts verbal commands, and at no point she is shown reading anything or being introduced to the possibility of doing so, they spend time on that. The calling card is then used for a plot twist later, but it makes no sense that the thoughtful cop would give to a blind person without even asking if she can use it or giving the slight non-verbal hint that it was a blunder or problem.
Stupidity: People can behave irrationally at the horrible sight of a murder, however the first couple that happens on the first murder scene behaves in a completely silly way; the guy pulls over and instantly rushes out as if he already knew what happened roadside, and his partner screams terrified, but jets out of the car and towards the bleeding victim anyway. In fact, she opened the door even a second BEFORE he did. (00:07:30)
