Ayreon is a musical project by Dutch songwriter, singer, musician and record producer Arjen Anthony Lucassen. Ayreon's music is described as progressive rock, progressive metal and power metal sometimes combined with genres such as folk, electronica, experimental and classical music. The majority of Ayreon's albums are dubbed "rock operas" because the albums contain complex storylines featuring a host of characters, usually with each one being represented by a unique vocalist.
Each Ayreon album tells a different story, but all, with the exceptions of Actual Fantasy, The Theory of Everything, and Transitus, take place in the same fictional, science fiction universe; additionally, Lucassen's solo album Lost in the New Real is also set in the Ayreon universe. Ayreon's music is characterized by the use of traditional instruments in rock music mixed with instruments more native to folk and classical music. Lucassen writes the music and the lyrics, sings and plays most of the instruments on all of the Ayreon albums, alongside many guest musicians. His most regular collaborator is drummer Ed Warby.