As a huge Batman fan, I was excited to see the first part of The Dark Knight Returns which was based on Frank Miller's comic. I loved it so I made sure I saw the final half as soon as possible.
The film starts out with the Joker regaining his consciousness after years of being in a catatonic state. When he sees Batman's return from retirement, the Joker decides to give Batman (and Gotham) a series of terrible events. He eventually leads the Dark Knight into an epic battle that will settle things between the two.
But Batman also has to deal with the fact that James Gordon has retired as police commissioner. His successor Ellen Yindel has declared a war on Batman, but that's not Bruce Wayne's biggest problem. His return from retirement has been noticed by the President of the United States, and Superman (the only approved superhero remaining) comes to tell Bruce that if things don't change then a battle between Batman and Superman will be inevitable.
I thought the second part was an epic conclusion to the story. I really liked Joker's part of the tale, and thought this was one of Superman's finest moments. Two epic battles, and some of Batman's greatest actions make this one of my favorite films of the year.