We interrupt your regularly scheduled program to announce that the blackout in downtown Gotham seems to have spread to the rest of the city. Lights in the street will have mysteriously blown out, and nothing running on electricity will be working unless it has its own power backup.
Like the laptops for example. Handy that.
Anyone wandering around the streets may also now and then come across someone...slightly charred and crispy. Not too sure what happened there. You might get a story of a strange person in black from them. A mugger of some sort?
...although the slightly stranger tales of lightning strikes might make that idea get dismissed fairly quickly.
The local authorities aren't too sure what's causing this yet, but they will get back to you with details later. Provided...they actually find something.