Fire-alarm pulling?

LATimes:

Ketchum could remember only one out-of-character incident.

"Someone pulled the fire alarm next to my door," she said. "We all were told there is an invisible dye that squirts onto your hand when you pull the alarm and you're not going to be able to hide. And Sarah looked at her hands, and said, 'Oh my God, look!' And she went and confessed."