It goes without saying that anyone who is interested in reading graphic novels should read Neil Gaiman's groundbreaking and seminal work, "The Sandman," published by DC Comics on its Vertigo imprint. They also should read the related works, including two trade paperbacks about Death, one about Destiny, and a collection called "Endless Nights," all by Neil Gaiman, save for "Destiny: A Chronicle of Deaths Foretold." I can't recall who wrote that one, but it had a haunting, funereal beauty about the lives of those who become entangled with a man marked out by Destiny for horror.
Other graphic novels worth reading, in no particular order:
1. "Strangers in Paradise," by Terry Moore. (This is a series of about 17 collections so far). The series follows the lives of two women, Katchoo and Francine, and one man, David Qin. It gets melodramatic and soap operaish at times, and there are other times Moore has lost track of continuity and what he's doing, but the writing is nonetheless excellent.
2. "Batman: Year One," by Frank Miller. On no account should you read "Batman: DK2." It *really* sucked.
3. "Daredevil: Born Again," by Frank Miller. The Kingpin discovers Daredevil's secret identity and proceeds to destroy him.
4. "V for Vendetta," by Alan Moore. Set in an England under fascist rule, this graphic novel shows the rise of the human spirit and longing for freedom, embodied in the anarchist V.
5. "League of Extraordinary Gentlemen," by Alan Moore (two volumes, barely related to the movie). The British government begins assembling a team of people known to us from 19th-century Victorian literature, including Mina Murray, Allan Quartermain, Captain Nemo, Edward Hyde and the Invisible Man. The series is worth reading just for the sly references Moore sneaks in to other literary works. Volume one establishes the team; volume two takes place during H.G. Wells' "War of the Worlds."
6. "1602," by Neil Gaiman. Gaiman transplants the classic Kirby-Lee characters for Marvel Comics from 20th-century America to Elizabethan England. Despite the large ensemble cast, this is a story not to be missed if you're familiar with the Marvel icons.
7. Marvel Legends Thor 1 & 2, by Walt Simonson. the start of a fantastic and defining run on Thor back in the 1980s, this actually includes the start of Ragnarok, the Twilight of the Gods. Absolutely incredible stuff.
8. "Amazing Spider Man: Coming Home," "Revelations" and "Until the Stars Turn COld," by J, Michael Straczynski, of "Babylon 5" fame. Unbelievable. The guy reinvented Spider-man in the first set, and set Webhead's entire world on its head in the second one.
9. "Rising Stars," by Joe Straczynski. A realistic look at the superheroes, used as a metaphor for lots of stuff, including limited natural resources.
10. "Kingdom Come," by Mark Waid and Alex Ross. Set in Superman's post-retirement days, this comic brings Superman and the rest of the Justice League out of retirement to battle a phalanx of brutal antiheroes who have taken their place in the years since they left. It closely follows the book of Revelation.
11. "Marvels," by Kurt Busiek and Alex Ross. The history of the Marvel Universe, from WWII up through the death of Gwen Stacey, told from the point of view of a news photographer who is not Peter Parker.
12. "Astro City," by Kurt Busiek. This is at least three volumes long. It deals with a superhero universe built with elements of DC and Marvel so that Busiek can explore those heroes by proxy. It deals with things like what would a superhero do if his time were his own, how a superhero has to balance his family responsibilities with his obligations as a hero, what makes someone a hero, and so on. Also good stuff.
13. "Midnight Nation," by Joe Straczynski. An L.A. cop loses his soul and has one year to get it back. A great parable about our nation's coldness to those in need.
14. "Black Orchid," by Neil Gaiman and Dave McKean. Gaiman picked a relatively unknown superheroine -- heck, I never even heard of her before I read that volume -- and did some interesting stuff with her. It's definitely not a superhero story, which is always nice in comic books, and it starts to lay some foundations for Gaiman's theology of the plant kingdom, which he was going to develop more in "Swamp Thing" if he ever wrote that comic, which he didn't.
15. "Ronin," also by Frank Miller. That's the story about a reincarnated Ronin (a samurai, who by failing his master, allowed him to die) going toe-to-toe with a demon in a futuristic New York. Sort of. But not exactly. Not at all, really, but I can't say why not without giving away important parts of the plot.
And if anyone is overfamiliar with the superhero genre and wants to read a brilliant sendup, I recommend the "Quantum and Woody" series published by the now-defunct Acclaim Comics.
I skimmed a collection of Frank Miller's "Sin City" a while ago, and found it unengaging, but that's me personally. I don't care for film noir and gangster movies, which is what Miller was imitating, although I do enjoy Miller's older material immensely.
Also, I forgot to mention Jeff Smith's "Bone" series. It starts out as a kid-friendly humor comic, and although it retains its kid-friendliness and a strong humor vein, "Bone" definitely attains the air of high fantasy. Highly recommended.
And then there's "Cerebus." I bought the first volume of that on a recommendation, but found it so unimpressive that I've never bothered to pick up any of the later volumes.