You've got to get obsessed and stay obsessed

I actually do usually say something along the lines of "Even though I am not familiar with the original, I really liked X, Y, Z." I mean mostly likely a person would enjoy it better if they were, but unless you plan to go back and read all the originals, you're kinda stuck. LOL It's possible some won't need that kind of comment but if you say, "Wow, I loved ABC!" and it turns out that is directly from the original, that's a bit embarrassing too.