Abby actually did play theaters after the lawsuit
So, the story goes like this: Warner Brothers sued AIP for similarities between "Abby" and "The Exorcist". Depending on where you read about it, it's reported that Warners had it pulled from theaters and all prints confiscated, resulting in it being considered a "lost" film until someone found a 16mm copy somewhere. The unofficial DVDs in circulation today are all made from this 16mm print, so that's why it doesn't look all that great.
I have been going through old newspapers from different cities and saving ads for horror/exploitation films. I always find "Abby" playing theaters starting in December 1974, and in many cities it was successful enough to be held over two or three weeks. HOWEVER... currently I'm looking through the papers for Spartanburg, South Carolina, and lo and behold I found "Abby" playing there several times over the years AFTER the initial run, which means it was after the lawsuit. The most recent exhibition was October 1976, although I'm not finished with Spartanburg so there may be more.
Also, for the record, I can't understand why Warner Bros got so bent out of shape over "Abby", other than the fact that it was making money. There were countless "Exorcist" ripoffs released in America that Warners did not take legal action over, most notably "Beyond the Door", which actually contained even greater similarities with "The Exorcist" (like Juliet Mills vomiting green bile and her head turning completely around). People claim that "Abby" is a scene-for-scene ripoff of "The Exorcist", which is not true. There are thematic and visual similarities, and there's only so much you can do with a story about anybody possessed by a demon, but it's nowhere near as similar as some people say it is.
Ironically, one of the programs I found "Abby" playing on was a double feature with "Beyond the Door" in January 1976. I can't post pics here, but if you like looking at vintage ads for horror/exploitation films, you should follow my page on Facebook, Groovy Doom.
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