Did someone say cosplay party? Hang out with Cassandra Clare and Holly Black while they sign copies of their bestselling novels.

Cassandra Clare is the author of the #1 New York Times bestselling Mortal Instruments series. She is also the co-author of The Iron Trial, book one in the Magisterium series, written with Holly Black.

Holly Black is the best-selling author of contemporary fantasy novels for teens and children. Some of her titles include the Magisterium series (with Cassandra Clare), The Spiderwick Chronicles (with Tony DiTerlizzi) and the Modern Tale Of Faerie series.

Prizes on the day for best costume!