"Time for the real detective work now, huh?"

She flashes a brief smile, then tilts her head and furrows her brow as if thinking hard.

"I only got here about half an hour before i ran into you, and found out about this thing about twenty minutes or so ago - wait, that doesn't help us out at all."

"The time of the incident..."

"The building only opened a half hour ago, but it had already happened by then, so -"

"Sometime overnight? There's no way anyone working late or cleaning wouldn't have noticed it, though. So, sometime when the building was supposed to be closed?"

She grins, proud of herself for figuring it out. You don't have the heart to tell her that her "discovery" is too vague to be of much help at all.