Amnesia

Your favorite eccentric professor has invited a group of his students to his home to celebrate the end of the semester. But you wake up in the middle of the night in a cold sweat, with no recollection of what happened and still under the effects of what you were dosed with. The professor is missing and you realize one of his patients is behind all of this. Can you piece together the mystery of what happened to save yourself and your professor before time runs out?