I've never had this happen before. Usually when a disc is a dud it announces the fact from the word "go".
The movie was Bunuel's Diary of a Chambermaid. Jeanne Moreau is a hard-faced city girl who gets the better of a village full of fascists, rapists, liars and cheats by being smarter than they are. At least I think she does, but how can I be sure? The last I saw of her she was making an advantageous marriage to the thoroughly despicable colonel-next-door...
But what happens next?
I seem to remember a story (maybe it was by Thurber) in which a guy reads a mystery novel only to find that the final pages are missing. It becomes an obsession with him to discover the ending. He scours libraries, second hard book shops, all to no avail. Finally- probably when he's on his death bed- he learns that the author of the book died without finishing it.
Well, I'm not in danger of developing that sort of thwarted obsession with Chambermaid. Other copies are available. The ending is out there.
Even so, I've now got this itch that needs scratching.