Grzegorz Kupczyk is a Polish singer, musician, arranger and producer. Between 1982-1989 and 1996-2007, he was the vocalist of Turbo. In 1989, together with Maria Wietrzykowska, he founded the band Ceti. He also cooperated with Esqarial, Chainsaw, Kruk, Non Iron, Aion, Red Pink, Panzer X, Wieko. In 2007 he made his last tour with Turbo as part of Metal Marathon, and then left Turbo for the rest of his life, devoting himself entirely to his band Ceti. In 2009, Daniel Wolak's book entitled "The Band" was published. In 2009 a book by Daniel Wolak entitled *Spiedź Grzegorza Kupczyka* was published, which is a biography of the vocalist. In 2012, for his outstanding contribution to national culture, he was honored by President Bronisław Komorowski and the Governor of Wielkopolska Province with the Golden Cross of Merit.

Anja Orthodox is a Polish musician, singer, songwriter and composer. Orthodox is best known for her long-lasting performances in the band Closterkeller, which performs music from the borderline of rock and gothic metal. She has also cooperated with such bands as: Wilki, Sweet Noise, Voo Voo, Abraxas or Ira. She is called by the media "the first lady of Polish metal and gothic".