I wasn't disappointed when I saw DragonBall: Evolution, the Western live-action film based loosely on the DragonBall series. That's because I expected a horrible movie and only watched it out of a morbid curiosity. I was disappointed, however, when I saw Samurai Deeper Kyo and it sucked. That's because I loved the manga and had been looking forward to watching its adaptation since volume one.
This week's discussion question: What's the most disappointing manga adaptation you've ever seen?
(I never read or saw Samurai Deeper Kyo, but a random message board post proclaimed it to be an unworthy adaptation, so I faked it. Sorry.)