Art Spiegelman's Maus was one of the most difficult graphic novels I've ever read.
Not difficult because of the subject material- though it's hard to think of a book about the Holocaust as light reading.
Maus is hard to read because it's literarily hard to read. The colorless frames have very little gray; what might seem to be gray at first glance is in fact minutely cross-hatched black and white. This leaves the eye (or, at least, my eye) very little time to rest.
As a story about storytelling, hardly a frame goes by without a word in it, and in most frames, the words overlow. The dialogue bubbles interfere with the images; there's just not enough room for the words and images to co-exist. If that's not trouble enough, Spiegelman's hand printed writing slants and tumbles just enough to make it impossible to scan. Every page is a labor (and maybe it's supposed to be that way).
While the anthropomorphized animals might give a reader the emotional distance to deal with the tragedy (and while Jews-as-mice, Nazis-as-cats motif might help a grade school student keep track of good guys and bad guys), the truth is that none of the main characters are drawn distinctly enough to help me keep track of who's talking to whom across the disjointed and often interrupted narrative. Spiegelman's play on traditional expectations of animals in comics was subversive at the time (compare these Holocaust surviving mice to Donald Duck, Mighty Mouse and Garfield), the artifice doesn't hold up. Comics have come a long way in being appreciated as an artform since Maus won the Pulitzer Prize in 1992.
Am I harder on Maus than on so many other graphic novels because of how highly recognized and praised it is? Yeah, probably.
I mean, Maus has everything I love in a novel.
Start with the framing tale, the son talking to his father, and his father's story relayed across a barrier of language and years. It's so Heart of Darkness that I could just about squeal with joy (would that make me one of the Polish pigs?).
There are questions built into the narrative about the power of memory to contaminate life, the power we allow our families to have in shaping our adult lives, the difficultly of finding a space of our own as children that still shows sufficient respect for the sacrifices our parents made to bring us this far. Plus, as a graphic novel without anyone wearing spandex, Maus meets one of my personal criteria for graphic novel greatness.
But while Maus partnered with Watchmen and The Dark Knight Returns in the late '80s to bring comics for adults into the mainstream, the other two book are just so phenomenally more readable, that I have a hard time imaging I'll ever pick Maus up again.