Batman: Year One - (Batman # 404-407, 1987). This story by Frank Miller with art by David Mazzuchelli redefined the Batman mythos. Here is the definitive post-crisis origin tale confirming Batman as the Dark Knight, distancing him further from the campy 1960s TV series and the 1950s sci-fi era. It's fairly consistent with Dennis O'Neil's run as Batman writer in the 70s and O'Neil just happened to be serving as editor during Miller's four-parter.
I can see where this story influenced the movie Batman Begins. We have police lieutenant James Gordon, before he was Commissioner, a good cop fighting corruption in a big city police department. Bruce Wayne has just returned after twelve years abroad preparing himself as the supreme crime-fighter and vigilante of Gotham. Also, like the movie, the police surround Batman in an abandoned building where he uses special technology to summon the bat population.
The gritty realism is what I've always liked about Batman since the O'Neil days. I prefer to see him fighting gangsters as opposed to members of his rogues gallery. In this story a highly trained, yet inexperienced Batman struggles his way through. The human element comes through in Gordon's relationship with his wife and his detective partner.
This story, since reprinted in hardcover and various trade paperback editions, is one of the best Batman stories ever. I felt as if I was watching a movie while reading this truly suspenseful comic. I love Batman in any incarnation, but the Dark Avenger of the Night is how he was meant to be from the start.
Now here is some good news. Batman: Year One is going to be a made-for-DVD animated movie released later this year.