Most of the comic deals with Harley’s inner struggle at what she’s about to do, her conflicted memories of Mr. J., and the conversation between the loony bird (and I mean that affectionately) and the one guard left in her way.
It’s an interesting scene as Harley disarms him, using the guard’s past as the weapon she needs to gain access to the Joker’s cell. And there she finds nothing, except her own twisted feelings, standing between her and the Joker. Even if the conclusion is a bit obvious, the buildup works quite well.
There’s also a B-story as Poison Ivy and Catwoman bicker over whether or not to help their friend. Ivy throws down an ultimatum which Catwoman ignores. Is this the end of the Sirens as we know them or will Catwoman risk everything to help her friends? Worth a look.