Oh man. Okay, first off, I'm a huge Coheed fan. There will be more than one album on this list. IKSSE3 changed my life in high school. The first song I ever heard was A Favor House Atlantic in the summer of 2004, on a local radio station. I had no idea what it was called and spent months searching for that song and never forgot it. In the winter that year The Zone played it again and I squealed with ecstatic joy. That was my introductory album - I YouTubed the hell out of the band and IKSSE3 became the soundtrack to my freshman year in high school. The lyrics made a whole bunch of no sense to me. It wasn't until I was 20 that I did some more Googling and found out - holy shit, this band has a comic/graphic novel/novel series that goes along with the albums. My mind was blown. I bless this introductory album which has now got me inked permanently with a Keywork and a dragonfly.
Song to check out: A Favor House Atlantic