.E.G.I.S., the Advanced Expert Group for Intervention and Security, is the premiere superhero law enforcement agency in all of Halcyon City. Its power is enormous; its actions, dangerous; its goals, secret. The agency is both respected and feared in equal measure. Now their secrets are laid bare for you. Cracked files, mission reports, and more await you within. Secrets of A.E.G.I.S. is a sourcebook for the roleplaying game Masks: A New Generation that fleshes out the metahuman covert law enforcement agency, A.E.G.I.S., with new details and new ways to play the game. Masks: A New Generation is an ENnie-award winning superhero roleplaying game in which a team of young heroes fights villains, saves lives, and tries to figure out who they are: noble paragons? Dark avengers? Or regular kids? All against the backdrop of Halcyon City, the greatest city in the world and home to the Advanced Expert Group for Intervention and Security—A.E.G.I.S.