I was thinking of the Daedric quest for Sanguine which has nothing to do with the Brotherhood. Sanguine sends you to a party and wants you to use a spell without telling you what to do. Tap for spoiler
Ah ok. Because of the dress rules in the title, I thought it was about that one countess's party you have to crash.
I always wondered, was it the sun it the cry of the rooster that killed Orlok in the original Nosferatu?
They prefer to be a disembodied hand that comes out of a box.