In a special anniversary story, 'Harley Saves the Universe!'-no kidding! While reading a mysterious Harley Quinn comic book, H.Q. accidentally breaks all of reality. And you know the saying: if you break it, you bought it! Now it's up to Harley to travel through both time and space to fix all the continuity errors she created. Luckily, she'll have a little help, 'cuz riding shotgun is none other than special guest star Jonni DC, Continuity Cop! Good thing, too, because if Harley fails, it means her own mom will be lost forever. Gulp! That doesn't sound very funny!