Not bad, though the gag about Katana's safety suit in the opening was overboard. I'm not surprised that her look is just her standard outfit with a domino mask; they've spent seven weeks establishing that look for her in our minds, so I didn't expect them to depart from it much now. Plus it saves them having to build a whole new digital model for her.
Barbara is still cool. I loved how she kept talking back to Whale, being thoroughly unimpressed by her own kidnapping. And I loved "When can I get a grapnel?"
Not too convinced by the origins of the Batsignal. With his daughter under threat, you'd think Gordon would've wanted to contact Batman more clandestinely, not in a way the whole city could see. Not sure how he would've managed that, though.