Seems like the teaser trailer leaked online, and up onto YouTube, though it has since been removed by Warner Brothers because of copyright issues. To be honest, there’s not much to see, just some streams of light.
Here is the transcript:
Bruce: “I knew the mob wouldn’t go down without a fight. But this is different. They crossed the line.“
Alfred: “You crossed the line first, sir. You hammered them. And in their desperation, they turned to a man they didn’t fully understand. Some men aren’t looking for anything logical. They can’t be bought, bullied, reasoned, or negotiated with. Some men just want to watch the world burn.“
Joker: Starting tonight, people will die. I’m a man of my word. [Laugh]