Several years ago (note: not five, not six, several ...*cough*) Chicago was a different place. There were vigilantes, and then there weren't as they started getting killed off... not Slipstream though, he's still there, saving people, OH NO! He's dead now. A knife through the chest by a serial killer usually does that.
In the present, Dick is still trapped by the Prankster, but uses a foam pellet to put out the fire, and then comes crashing through the glass, and listens closely to determine where Prankster is, throws... that string with two balls at the end, whatever that's called, and there you go, one trapped Prankster.
Dick has use of the Prankster though, which he doesn't get to explain due to the Chicago PD showing up. Dick asks his foe if he can get his optics back online, and suggests that he's the Prankster's best chance of getting out of there. Prankster, not being dumb, agrees, and once Dick drops some smoke bombs, he turns the optics back on, which allows Dick to deal with the police so Prankster can escape and "wait" outside.
Well, Prankster gets to the roof, but has no intention of waiting for Dick... but Dick knows that, shows up, and decides he's not going to let Prankster be conscious anymore. Elsewhere, Tony Zucco and his new family are getting ready to go on a last minute vacation, as headlines of a Gotham vigilante in Chicago are all over the papers.
Prankster wakes up to Dick watching him, while enjoying some coffee and donuts. Dick has a proposition for him, he needs help finding Zucco, and the Prankster's advanced computer skills are what will come in handy. In return, the Prankster gets Dick to agree to stop hunting him. While Prankster gets to work, we see Dick's new roommate being contacted by a detective who gives him one of Prankster's cameras which should work as a career advancement of sorts for him, yeah, we'll have to see on that one.
So, back to Dick and the Prankster... the computer hacking has worked, and Prankster has found an IP address, but he's also noticed that while in an Illinois jail for a couple years, Zucco came in contact with Mayor Wallace's brother... Combine that with the fact that the IP address is coming from City Hall, Prankster deduces that Tony Zucco is going by the alias of Billy Lester. With that in mind, Dick handcuffs Prankster to a pipe and takes his tech glove, as he was never really going to let Prankster go, just stop hunting him, which wouldn't be a problem if he was in jail.
Dick finds the empty apartment of Billy Lester, which seems very off to him, as it's not befitting of Zucco at all. But sure enough, Dick finds a photo of Zucco... with a family. That definitely complicates things and confuses Dick, quite a bit. Meanwhile, the police find an empty roof, with Prankster nowhere to be seen...