Now normally, I wouldn't pick a low budget B horror movie for a question like this...but I have no choice.
A Virgin Among the Living Dead
They trick you with a picture of this nearly naked large breasted woman on the box, and she is surrounded by a horde of zombies.
While still obviously, a B Horror movie, that looks kinda intriguing.
Then you put the movie in....
There is one chick (who is ugly) and two dead people, that is all.
To make matters worse all they do is talk for 90 minutes. Just Talk....
Then for the raging climax, one of the dead guys slaps the girl across the face. That's it...he slaps her, she leaves, the end.
To make this just a little bit worse, she throws her head the wrong way on the slap.
He is standing in front of her, and slaps her across the left cheek, with his right hand..which would cause her head to be thrown to the right....but she turns her head left.....
Worst Movie Ever
:Honorable Mentions:
Queen of the Damned
Plan 9 from Outer Space
Devil in the Flesh