The past four days have been a non-stop party for a lot of fashion people here in New York. And those Halloween parties have been well-documented. The Tribeca Grand's Overlook Hotel party, the Boom Boom Room's fete and last night's V party hosted by Terry Richardson drew the most fashion-heavy crowds and, as we all know, fashion people like to dress up. They also seem to like obscure references--many of their costumes were tough to identify, but still fun to look at. So, from Alexa Chung to Joan Smalls to Marc Jacobs, here are a bunch of fashion people in their Halloween best!