2. Kingdom Come (Mark Waid and Alex Ross)
Kingdom Come is a seminal JLA story which brings together the immense aforementioned talents of Alex Ross and the genius-level storytelling prowess of Mark Waid. I mean, what more could you possibly ask for? Another epic super-war story, Kingdom Come is set in a possible DC future in which heroes like Superman, Batman and Wonder Woman have been largely replaced by a new generation of dangerous, amoral super-powered vigilantes who threaten to inadvertently destroy the world in their eternal conflict. True, the whole future setting would probably be out of the question for a Justice League movie but with a few minor adjustments there are plenty of opportunities for this book to be successfully referenced. For example, the Kingdom Come hinges on the authoritarian approach that Superman takes toward this new generation of super-beings and the idea (put forth of course by Batman) that his traditional values and methods may be outdated and worse, may threaten to exacerbate the situation entirely in the light of an ever-changing world. In the Justice League Film, I'm keen to not only see the League face off against an ultimate foe, but to see how each hero within it deals with the inevitable friction caused by the gathering of a group of super-powered beings and of course, super-powered egos. No JLA story - none that I've personally read anyway - discusses this idea as beautifully as Kingdom Come.