Death at Black Marble Quarry

From the introduction: Black Marble Quarry is a recent attempt at expanding production within the local region. The quarry’s eponymous black marble is extremely rare, with only a few reliable mines located around the world. The mine was also designed to serve a secondary purpose: as a privately run penal colony. Quarrymen are prisoners sent to work the quarry as punishment, with their living quarters located off-site. The quarry has been running more or less smoothly for the better party of a year, but suddenly the entire quarry has gone silent. Kingdom officials have been sent to investigate - yet all have failed to return with news. Finally, with no other choice, the kingdom has started to send private adventurers to investigate and return the mine to proper working order.