Rob thumbs a glowing 22. The elevator groans up, and he idly reaches out to flick the handbar. It bells a tone, strong and clear. No telling what note, but it’s practically a tuning fork.

Rob pings the bar on his left, then the one on his right: more notes, just as definite and pure. He hesitates, then hits all three in sequence. The reverb catches him in a minor chord.

Sound and car stop abruptly. Rob squints up at the dial.

An old building–he didn’t stop to think. But now the car says it’s nowhere, between 12 and 14.