Brandon Mull will sign the final volume of his New York Times bestselling series, Fablehaven: Keys to the Demon Prison on Tuesday, March 30 at 6:30 p.m. at Barnes & Noble on 4100 Summit Plaza Dr. in Louisville. In this explosive series finale, allegiances will be confirmed and secrets revealed as the forces of light and darkness collide in a desperate struggle to control the keys to the demon prison, Zzyzx.