This is fun! A supposedly leaked trailer billing itself as "Batman: Arkham City - Warner Bros - Fight Trailer" has made its way to French video-sharing site Kewego. The approximately 2-minute clip features our fearless Dark Knight beating up baddies with ... the Joker? Putting aside our canonical concerns about the caped crusader clobbering criminals with the clown prince of crime, a few other things raise immediate bat signals.

Join us after the break for our best world's greatest detective impersonation as we piece together the clues and reveal the truth about this "Fight Trailer."