Stuck for a scary Halloween costume?
Don a comedy beard and strap loads of fake dynamite to yourself under your coat and silently in the middle of the room, undo your coat and shout "Allah Akbar!" at the top of your voice.
Guaranteed screaming - you'll be the most scariest.
NB: keep the costume in a holdall and change outside the party... that could be a life-limiting costume on public transport!