My favorite was back in the early 1970s, and the film, Secret Ceremony, was shown on network TV. This obscure (and deservedly so) movie stars Liz Taylor as a prostitute who picks up a mentally challenged/insane Mia Farrow. They engage in sexual role playing games, eventually with Robert Mitchum who may or may not have been Mia's father, and who may or may not have been Liz's former customer or lover. One of those trendy movies where not much happens, and next to nothing makes sense.
So the network censors created a whole new movie, using outtakes and lots of voice over commentary to make Liz a hat model (?what?
?), and Mia her long lost daughter (in the original, Mia does claim this, but then she is supposed to be insane; in this version, it is absolute fact). Long scenes where the only soundtrack was the narrator talking on and on, desperately trying to make the movie be something it wasn't: coherent and G-rated.