The cauldron had not erupted as one might have expected from a volcano, but it had still been rather Vesuvian in nature, its contents making a steady and inescapable progress towards its keeper, resulting in a shocking shade of puce staining the front of the robes of Miss Regina and sending the Hufflepuff to the hospital wing with tears streaming down her face. Jameson had felt bad for his yearmate, and had offered to stay a little longer, clean up her station and put away her supplies.

It was a decision a small part of the Ravenclaw regretted now; he was one of only a few students remaining. One pair had been directed to reclean their station, having not done so well enough the first time, and another classmate had successfully freed themself only to come back, having left one of their books in the store room.

They might never have known which one of them jostled the door just so, beginning its gradual closing. Perhaps it might even have been Peeves, though Jameson had learned early in the year that the poltergeist was not the sort to keep quiet about his anticis. It may simply have been a draft, or ill luck. Whatever the cause, the Ravenclaw heard the problem before he saw it, the door clicking itself quite deciedly shut and plunging the youngsters into darkness.