Sometimes there is exceptional acting in our favorite movies and tv shows. And sometimes, there is...well, bad acting. I mean, really bad acting. It doesn't matter if the person doing the bad acting is usually good and they had a off day or role, or if they are a novice and this is their first acting role, or they were always that bad. Bad acting can even ruin an entire movie or episode, end careers and just screw up everything.

Example: Megan Fox in Jonah Hex.