After finding the word 'MATER' written on the leather case, in the next scene Mark is unpacking books and placing them in piles on the desk. Poor editing makes it appear he is removing them from a case with the storage capacity of Felix the Cat's bag.
Towards the beginning, when the character played by Irene Miracle is swimming through the lost cellar room, she clearly is not wearing a bra; however, a few minutes later, after surfacing and returning to the building lobby, you can see that a bra has magically appeared under her dress.
In the scene where Kazanian is investigating a noise in his shop, he is shown reaching towards the table closest to him. As he's reaching down, his right crutch falls from under his arm. However, in the next mid-shot of him backing towards the bookshelf behind him, the right crutch is just starting to fall from under his arm.
When fleeing a library, a woman's blouse gets torn on a door handle. She tells a man in the elevator she is afraid, which he believes because he has noticed her torn blouse. When they enter her apartment, the blouse isn't torn.
When Sara gets out of the taxi at the library her hair and blouse are drenched in the rain. The very next scene where she walks into the library, her hair and blouse look almost completely dry.
When the power begins going on and off in Sara's apartment, the music continues to start and stop as if a CD was playing. Since she is playing a record on a turntable, there would be slowing down and speeding up as the power goes in and out.
The scene at Central Park takes place during a lunar eclipse. However, the eclipse mimics the aesthetic characteristics of a solar eclipse with the Moon being completely blacked out, surrounded by a corona, just as if something had moved between Earth and Moon. However a real lunar eclipse doesn't appear to be pitch black but as a dark reddish layer and there certainly isn't a corona which is a feature of the sun.
A man uses an electronic voice synthesizer to talk, it becomes unplugged during a struggle, but he continues to speak in the mechanical voice. Actually, if you watch carefully, Mark plugs the microphone jack back in after untangling him so the man can speak again. He cannot speak without it, and Mark obviously wanted an explanation.
When the girl and the man are shown talking behind the door and we see their silhouettes, their mouths clearly don't fit with the words spoken at the moment.
During the cat attack, a human hand can be seen throwing some cats at the actress.
When Marks finds a hole in the floor, when the cat jumps in the hole, a human hand can be seen grabbing the cat under the floor when it lands in the hole.