As luck would have it, in one of my Comparative Literature classes, we are currently reading the extremely well regarded graphic novel Watchmen. This happens to coincide with the release of the film version of the graphic novel. This is my first go around with the reading of it, but as I have read throughout various websites, this is considered the unfilmable comic book.
For those unfamiliar with Watchmen, the story takes place in an alternate 1985, a world where costumed superheroes do exist. Each of the story's heroes bring a number of flaws behind their masks, presenting a sense of realism and avoiding giving us the well liked perfect hero. It was a twelve-part series that many considered unfilmable due to it's length and the amount of detail in each of the novel's drawings, giving the reader a sense of what the world of Watchmen is really like. Below is the movie trailer. It remains to be seen if the movie as a whole is well executed, but the trailer gets me excited.