Tuomas Lauri Johannes Holopainen (born 25 December 1976) is a Finnish composer, songwriter, keyboardist, and producer, best known as the founder, primary songwriter, and creative visionary of the symphonic metal band Nightwish. Widely regarded as one of the most influential composers in modern metal, Holopainen is recognized for blending metal, classical music, film scores, folk, and progressive rock into expansive, emotionally driven works.