But never mind all that. They showed it to a priest, a rabbi, a professor, their film critic, and a randomly selected reader of the New York Post. Which sounds like it could be the setup for a great "... walked into a bar" joke, but it's utterly wasted in this case, since the upshot is simply that most of them didn't like the film very much, citing the portrayal of the Jews as a particularly troubling point -- though the randomly selected reader of the New York Post disagreed on both counts, which is a little worrisome.
But there is still a joke. You just haven't heard it yet. The joke is that with all the other things the FBI has to do, they are nevertheless investigating how the Post got a copy of the film. But I'm sure they'd be doing the exact same thing if they'd all liked the movie. Aren't you?