Tuomas Lauri Johannes Holopainen is a Finnish songwriter, multi-instrumentalist musician, screenwriter and record producer, best known as the founder, leader, keyboardist and songwriter of symphonic metal band Nightwish. He has also studied jazz and classical styles, but prefers to be influenced by harmonic film music. He has also played in the bands Nattvindens Gråt and Darkwoods My Betrothed. His current side projects are the gothic metal band For My Pain... and the band of Timo Rautiainen. Holopainen has written several songs that have been included in movie soundtracks, including recent collaboration with Nightwish bass player, and male vocalist Marco Hietala on "While Your Lips Are Still Red", for the Finnish film Lieksa! in 2007. He also co-wrote Nightwish's own film, Imaginaerum, released in November 2012.

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