Batman saw the signal from across town, but it didn't take him long to get to the roof of the GCPD. He was expecting Commissioner Gordon, the person who usually summoned him for help.
At least, until the strobe experience began. By the time he got to the roof, he wasn't sure whether to be concerned, or annoyed. The sight of Impulse settled the matter: Annoyed.
Appearing over the boy in a billow of cape, keeping to the shadows so that none of his features could be seen, Bruce knew he made an imposing figure.
Good.
"Stop. Touching. That." His own hand reached out and flicked the light firmly off. Glaring at Bart, he didn't look up to address the other party.
"I assume you have a good reason for this, Flash."