We talked to some palace guards. Then was alerted to an unusual body in the dungeons which turned out to be Gibley’s acquaintance from Thief Club.
Based on the information available, we came to the conclusion that the murders were part of a larger plot led at least in part by the head of the necromancy department.
We decided to confront the necromancy department itself. We used the identification we had acquired from students to worm our way in. Working our way through the department we came to the office of the late department head which contained a large stack of gold bars. A voice from behind a door asked if were were The Master. We failed to bluff it, but Finn and Sorcha quickly dispatched it.
(There was some business about disease and blindness but we took care of that.)