Blooper

When Sylvia sits on the bed at Roberto's apartment after screaming and he tries to calm her down, her mouth is open, but in the very next shot, which shows her up close, her mouth is closed.

At the end of the movie, when people are arriving at the hidden place and medium enters, there is a clear cut before Roberto comes in.

Signor Rossetti moves after being killed.

Sylvia kills Roberto and drags his body, but he can be seen closing his eyes.

Sylvia moves her eyes while being dead at the table at the end of the movie.

Obvious fake finger when cats are eating.

Pack of "blood" is squarely seen under Roberto's shirt, under the cleaver on his back.