This is a really hard one to answer, I was surprised HOW hard. I don’t want to pick something TOO obscure in an attempt to be original, I just want to focus on what a comic book cover is really all about; which is A) standing out on the comic rack beside a hundred other covers, and B) something on the cover that makes you want to pick up the comic and read it. A lot of “runs” came to mind when I was trying to figure this out: Dave McKean’s run on Sandman, James Jean’s run on Fables, John Cassaday’s on X-Men, Frank Quitely’s on All Star Superman, and Frank Miller’s 300 covers. But at the end of the day I have to go back to what I initially said, and that’s what is the ONE cover that froze me in my tracks when I walked in to the comic shop? And I’d have to say that was Brian Bolland’s cover for The Killing Joke.
Bolland’s technical skill is amazing for starters, the simple use of bold color is also very effective, but the main reason is that the cover is interacting with the viewer, it uses a common experience: everyone’s had their picture taken, but this time it’s being taken by a sinister clown, his face is big and bold which also draws our attention, and when you read the story you realize how the cover is tied in to events in the comic, and the implication’s pretty creepy. “Smile.” Also it has possibly one of the best interior pages ever, so that seals the deal. It’s The Killing Joke.