Harley, fully clothed and not in a bath tub, is at the Secret Society's meeting with the Crime Syndicate, and is none too impressed. Order, meetings, these things aren't for Harley, Gotham is for Harley, and right now it's exposed, and she wants to have some fun.
Harley was raised in order, because her family was so dysfunctional and crazy, order is what kept her sane and focused on her studies, order is what allowed her to graduate top of her class and get the most prestigious jobs immediately afterwards. Then she met the Joker, and essentially fell in love with chaos, we all know the story, and as with the New 52 origin, she too took a dip into the chemicals, which truly freed her, and created a second persona to stand next to Harleen. Following that, we learn the origin of her new costume, part field hockey player, part hooker, part fast food employee, and chaos followed in Harley's wake.
Fast forward to a few days before the meeting with the Crime Syndicate, Harley is free of the Suicide Squad and she's having fun in Gotham, but first she has to give out free video game systems to all the boys and girls! Then she dresses up like a cop and visits a police station with quite a bit of dynamite.
Three days later she has a software update download to all the video game systems that turns them all into bombs, but Harley is still feeling a bit empty, maybe it's Harleen coming out of her a bit. This is where Deadshot shows up, having just gotten contacted by Waller who needs the Suicide Squad back together. Deadshot tells Harely they're both similar, bullets that without a target, are aimless and useless. Harley agrees, and seems like the Squad is getting back together.
Also, like the Mr. Freeze issue, I feel like we didn't really need to see Harley's origin again, but there was a little less retreading than The Dark Knight #23.2