"Yes, but we must find the wall on this side of the water that forms part of his house. Erik created many false entrances and exits down here so that he can move about unseen or disappear in an instant. As I recall. we can get in through one of them from over there."Raoul was dazzled by the display of flickering lights and images the mirrors created."Erik knows a lot about architecture and he actually helped build this Opera House. At the same time, he created this underground world for himself. I recognise his work, especially the trapdoors."A small door slid open in the wall and they crawled through to the other side, making their way slowly and cautiously.The Persian opened it carefully and shone his lantern into the darkness below.Raoul shuddered."Where are we?"