Tuomas Lauri Johannes Holopainen (born December 25, 1976, in Kitee, Finland) is a Finnish composer, musician and music producer. Despite being centered in heavy metal music, he has also studied genres such as jazz and classical. Holopainen is mostly famous for being the keyboardist, band leader, founder and main songwriter of symphonic metal band Nightwish. He has also played in the bands Nattvindens Gråt and Darkwoods My Betrothed. His current side projects are the gothic-doom metal band For My Pain... and the band of Timo Rautiainen.