It has been said ad infintum that Watchmen is the book that changed the face of comicdom. That without it, comics would still be for kids. While I think it is a monumental achievement in the history of comics and one of the medium's finest works, I am dubious as to it's importance to the common comic reader.
First of all, I present historical data, The Dark Knight Returns actually predates the Alan Moore opus by several months. This was certainly the first adult content book from a mainstream publisher that I read and I would imagine that this is the case for many readers from my age group. But it doesn't end there. With the onset of a mature reader The Shadow penned by Chaykin and the start of O'Neil's The Question as well as the proliferation of more experimental work by the publishing house of DC at the time like the groundbreaking Wasteland, it was more then just the one book but obviously a concerted effort by the publisher in general.
I am almost certain that this was a reaction to the success of independent comics that pushed the envelope from First's American Flagg to Comico's Fathom. Eventually we would see Marvel dip it's feet into the pool with various projects (was it the Epic imprint?) and the onset of it's Graphic Novel line saw it's mainstream universe Characters enter the realm of Mature Content. All of this led to the eventual start of the Vertigo and then the Icon lines as imprints dedicated to the more adult oriented reader.
All of this is kind of besides the poiint. The Query this time is:
What comic (or Graphic Novel) changed your perception of what a comic could be?
Having grown up in a period that allowed me to read the books mentioned as they were first published, their effect on me was not as great as it was to older readers at the time, so while I recognize the importance of those works, they are not the works that actually changed my perception of what comics were or their potential as a medium.
There are three books I can point to that did that for me. When I got back into comics about four years ago, I was mostly reading Star Wars books (which is funny because I don't read any of the current books).. a friend recommended two books to me. The first was Identity Crisis, while I understand the problems people have with this book, it was the one that really opened up the possibilities of the DCU to me. It has a weak ending but this is when I became entrenched into continuity books. Before Superheros had always been read by me in solo books. I read my brother's X-Men books when we were kids, but to be honest I never got the hoopla over them. I was all about Spider-Man and Batman. It was with IC[/c] that I really learned that a shared Universe was an awesome thing.
The other two books had a more profound effect on me. The first was recommended to me by the same friend, it was [i]Ex Machina. I picked up the first issue and was hooked forever, Vaughan eventually became my favorite comic book writer. But it was the saga of Mitch that spoke to me. First of all it was topical and I had never really read anything that spoke to me in a relativistic fashion before, certainly not like this book. It was BKV's way of excising the events of 9/11 not only from himself, but for a larger audience as well. Yeah it happened, but here was a vibrant city that had gotten over it. The other thing that stood out to me about the book was that Mayor Hundred was a regular person. He wasn't perfect, he had skeleton's in his past, he had no political background and no aspirations to be a hero, but through happenstance and heart he was able to lift himslef and those around him to a better place both personally and socially. It was cool to see someone that was so heroic and rational, but could cuss just like me and had been known to smoke a joint every now and then.
The last book is the doozy though. My brother first recommended Planetary to me. I was floored. The first issue I read was #22, where they torture William Leather. It a vicious book that spoke not only to a darker part of my subconcious but through the book's reference to a pop culture icon, the book was a way of building on things that had come before in a way I had never seen. I went back the next day and bought 19-21 and all the trades. I devoured them and have actually read the run a couple times since then. It was my first back issue project and the only one I have completed. The book tackles all the various forms of pop culture through out the years and examines them in its own unique way, but the done in one nature of the stories themselves and the way they worked together to build an extermely complex puzzle that has strung me out for four years for 5 more issues are unique. Its ability to remain fresh in my mind and demand more attention from me is sets it apart from any book before or since.
Anhow, that's my nickel's worth on the subject, what have you got?