I first stumbled upon TDKR when I was in elementary school, probably third grade or so. Admittedly it was a bit mature for a kid of that age in retrospect but I loved it because it was completely different than any other comic I had seen up until that point. It was dark, dangerous and just awe-inspiring. It was everything a comic should be. I still love this book to this day.
TDKR along with Arkham Asylum are my two favorite Batman books to date.