In case 2, Gumshoe says that Mask DeMasque always sends his calling card before a heist, but in the case's intro he's checking on something in a safe... and when he opens it, the calling card is inside. I got the impression that DeMasque stole something from inside and left his calling card. What else would Gumshoe be checking on?

He probably does both. Gumshoe was already there, so he must have known ahead of time and he does say they must have foiled the thief before they see the item missing. So there's one before and one left behind. Besides I think that was supposed to be DeMasque's first heist (the jewel), but I'm not certain. Pattern isn't usually established until later cases.

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Emanon.
And yes, that's probably what happened >_>

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