The Star Wars Holiday Special!

[Pentegarn]

This special was so bad it became an experience. I made a friend watch it with me when I got my copy, because for something this bad, one must not experience it alone.

And yes, Bea Arthur was probably the only real entertaining part of this special (no disrespect to Harvey Korman, but after Blazing Saddles, High Anxiety, History of the World: Part 1, and The Carol Burnett Show, I expect better from him, and you could tell he had little to work with and did even less with it)

EDIT: Side note, every copy of this I have ever seen has all these cool commercials from the 70s, and it doesn't take long till you look forward to these old commercials :P