The fact that nutmeg, in high enough doses, can cause hallucinations and psychotic episodes reminds me of "The Moonstone" by Wilkie Collins. Really, it's probably a good thing that not all Christmas parties are that exciting.
Countdown to Galapagos: 3 days!
Joanna awoke in the middle of the night, heart racing. Someone was in her room. She sat up and a wave of nausea and dizziness swept over her. She fell back and tried to calm down. The room was silent but she could sense someone in it, watching her. No, that was impossible. She would have heard breathing; the creak of the floor as he entered. Her reasoning brought no comfort. She screamed.
No one heard.
Later, a friend would proclaim that the eggnog had been particularly strong. And Joanna accepted this, although it tasted of not Rum, but Nutmeg.