Watch the credits till the end (it's not like you have a choice, since you can't click through them) for a screen near the end that tells you what to do.

It comes before Madeline drops her (still unhelpful) comments. If you missed it, the only way to see it again is to play the endgame again and let the credits roll.

Oh, you don't want to do that? Frankly, I don't blame you. After you've been dumped back out to the desktop, start the game again, restore a saved game in Rosa's apartment, go to her computer, and use Ogle to search for "mastercriminal."

This gives you three options: bloopers from the voice recording sessions, concept art for this game, and photographs of some of the New York locations featured in this game. The Minetta is particularly interesting; I'd go to the Minetta in the game, but the one in the photograph looks like a dark grimy haunt that I'd avoid like the plague.