Arachnophobia (1990)

Continuity mistake: When Irv and Blaire are snuggled up on the couch, watching Wheel of Fortune, watch the big bowl of buttery popcorn they have. In the first shot it is full to the brim. In the next shot it's half full. (01:18:15)

Hamster

Continuity mistake: When Jerry Manley is shown in the coffin his head is on the right side. When they show the shot inside the hole before inserting the poles, his head is on the left.

Continuity mistake: When they perform the autopsy on the three victims, Metcalf is all grey and stiff, whereas the two exhumed victims look alive and fresh.

Continuity mistake: When Becky is in the shower, the position of her hair as she washes it changes, and the amount of shampoo bubbles in her hair differs also. (01:09:10)

Hamster

Continuity mistake: Near the beginning, the clumsy guy walks backwards into a giant cobweb, so he is covered in it, but, as he leaves, there isn't a cobweb in sight on him.