1. In the official promotional trailer for the film, Abby appears in some scenes violently shuddering or convulsing through a computer-generated visual effect before attacking one of her victims, and also when she entered Owen's apartment without being invited in. However, this computer-generated visual effect of this trembling or convulsion has been removed from the film's scenes and cannot be found within the movie. Therefore, one star out of ten will be deducted.
2. Actor Richard Jenkins, who plays the character believed to be Abby's father or guardian, pours a corrosive substance on his face to conceal his identity from the police for an unclear reason. If he wanted to die rather than be imprisoned, he could have simply shot himself. If he wanted to both conceal his identity and die so that the police couldn't identify him after death, he could have detonated a hand grenade on himself instead of pouring a corrosive substance on his face, as it would erase his features without notable suffering. I don't believe he wanted to hide his identity and live disfigured for the rest of his life, as imprisonment without disfigurement compared to the torture of disfigurement by a corrosive substance would be a better option. Therefore, he had two better alternatives than suffering disfigurement by a corrosive substance until death: the first option being imprisonment without disfigurement if he was willing to have his identity revealed, or the second option of detonating a hand grenade on himself if he was unwilling to have his identity revealed. Nevertheless, he chose the worst, illogical, unrealistic option which the film failed to justify. Why to such an extent did he not want his identity discovered? If that would endanger Abby, then why didn't the film clarify that? Even if we assume the film did clarify that, the hand grenade option would still be better for concealing identity and dying together. Don't tell me he didn't want to die when he used the corrosive substance or that he didn't know it would torture him to death. He undoubtedly knew. So why die in agony when he could die without notable suffering? Nothing can explain this except that he wanted to punish himself for his sins of killing many innocent people. But since the film didn't clarify this, I cannot rely on this justification nor can it be considered valid. He should have said something before pouring the corrosive substance, such as "Let this be atonement for my sins," for this justification to be valid and for me to accept it. Since that didn't happen, another star out of ten will be deducted.
3. When Owen sneaked out to Abby's house, he had left his home while his mother was sleeping on the couch in the living room. No scenes were filmed showing his arrival at Abby's house, her welcoming him, what they did that night, and how he ended up lying and sleeping on the floor of Abby's house despite the existence of better places to sleep. For example, he could have slept on the couch in Abby's living room, but he didn't. Why not? The reason was never clarified!
4. After the police officer played by actor Elias Koteas entered the bathroom where Abby was sleeping in the bathtub, Abby killed him, and in a later scene, we find that the police officer's body was hidden in a hole in the wall of an apartment frequented by a boy who used to live in the building, named Tommy. This boy appears to be Owen's friend, otherwise Owen wouldn't have known about his secret hideout where he goes to drink and smoke with his high school companions. Or perhaps Owen simply discovered this information by chance because he often loiters outside and voyeuristically watches people through his binoculars in his room. So one way or another, Owen was able to know about this place. But the problem doesn't lie here; it lies in the fact that the police officer's body was hidden in this place in an absurdly ridiculous manner. It wasn't shown who did this, but it was likely done by Abby or with Abby's participation. It's inconceivable that Abby, who is accustomed to killing, would hide the body without covering the hole with anything, whether through cement, plaster, a piece of wood, or an amount of pillow stuffing and fabric. Leaving the body exposed in this way was illogical for a character accustomed to killing because there was simply no benefit to hiding the body in this manner. They went through the trouble of hiding it without any purpose; the smell would emanate from it in a short period and spread throughout the neighborhood, and neighbors would soon smell it and bring the police. I know that Abby and Owen escaped at the end of the film, but their escape won't last as long as the body will be discovered within a few days of their escape. The body will be linked to their escape along with the recent rumors circulated by investigators, and it will be easy to find a connection between them even if it doesn't seem logical for children of their age. Their escape will create a question mark that forces investigators to discover what lies behind it. Therefore, it was mentally unacceptable for Abby, who is accustomed to killing, to bury the police officer's body in this way, which would expose her escape operation with Owen to discovery and then destroy their future together.
5. Owen learning the language of tapping on things as a means of communication between him and Abby, with Abby's ability to comprehend the meanings of those taps without there being any notable introductions paving the way for such a thing to happen. We didn't see any dialogue scenes between Owen and Abby where one explains this new communication language to the other and teaches it to them. So let's say they learned it from the director behind the scenes.
