*Masks* isn’t a mystery game, and yet in game after game that I run, play in, or watch, there are characters finding clues, uncovering hidden agendas, and doing things that, on the surface, feel like the sorts of things you’d do in a mystery. But this is kind of a trap, or at least a thing to approach with extreme caution.
*Don’t* make people roll to find out key pieces of information—this is often dangerous in RPGs anyway, but especially in a game like this. *Maybe* there are rolls involved that answer questions like “what does it cost you to find this out” or “have you found out with enough time to do something about it, or at the last minute and you have to scramble—or find a way to time travel?”
What I find works best is this: instead of thinking about clues, think about *reveals*. These don’t have to be a villain monologuing, though that’s okay too. Fundamentally, these are *unambiguous evidence*, like “you step into the underground lab full of psychically controlled clones of the city’s elite”. Note, though, that they need not explain the *whole* plan—just the next step. Basically, “what’s next on the Arc the GM planned?”
Put another way: signal the escalations of the arc before you get there, but do so with flair. Let the players strive to stop that escalation, and if they don’t—make it. Do it. Escalate it. If they can put together from a few reveals what the ultimate goal is, *that’s fine*. Sometimes, the heroes figure out what the villain’s planning. But don’t *expect* them to or rely on it. And also, don’t pull it out from them—just because the heroes understand the villain’s goal, that doesn’t mean it’ll be trivial to stop it.