A dead body buried under a pile of ageing manuscripts. A secret chamber filled with a treasure-trove of books and paintings. Nat returns to Oxford in January, this time based out of the historic halls of Barnard College. When she agrees to meet Mathilde in the college archives after hours, they hope to find information on the magic. They don't expect to find a hidden chamber or stumble across another dead body. Nat is scrambling to figure out if this is a crime of passion, a case of wrong place and wrong time, or whether something larger is a foot. Meanwhile, Mathilde and Kate are searching the hidden chamber for information on the magic's origin. The last thing they need is Edward snooping around, wondering how the prefects are connected. Can Nat satisfy Edward's curiosity without revealing the existence of Oxford's magic? Can the prefects figure out how to restore Oxford's magical border before someone else dies?