Ayreon

Ayreon i is a musical project by Dutch songwriter, singer, multi-instrumentalist musician and record producer Arjen Anthony Lucassen. Ayreon's music is mostly heavy metal and progressive rock but combines them with genres like folk, classical and electronica. The majority of Ayreon's albums are dubbed "rock operas" (or "metal operas") because the albums contain complex storylines featuring a host of characters, usually with each one being represented by a unique vocalist.

source: Wikipedia