One of the problems with adapting old TV shows to the big screen is that the charm of the original is lost. Even if the show was ridiculously bad, we grew accustomed to the characters and the actors who portrayed them. We did so not because the characters were instantly memorable, but because they developed before our eyes, and we got to know them a little at a time over the course of the series. In a movie, we get a condensed, refurbished version of someone else's vision of the characters. More often than not, it falls flat.