A stalwart heavy metal bassist, vocalist, and songwriter, Marco Hietala is known internationally for his work with kinetic power metal group Tarot and symphonic metal heavyweights Nightwish. An in-demand producer and collaborator who has appeared on and/or produced albums by Delain, Amorphis, and Ayreon, among others, Hietala released his first solo LP, the hard prog-leaning Mustan Sydämen Rovio, in 2019. He is also a member of Finnish symphonic metal cover supergroup Northern Kings.

A native or Tervo, Hietala moved to Kuopia at the age of 15 and began studying classical guitar. Singing and music theory followed, and in 1984 he formed a band with his brother Zachary. Originally operating under the moniker Purgatory, the band adopted the name Tarot after securing a record deal. Their debut album, 1986's Spell of Iron, became an underground success on the strength of the fiery single "Wings of Darkness," which would go on to become the band's best-known song. Tarot enjoyed a modest level of popularity at home and expanded its audience in 2001 when Hietala joined popular symphonic metallers Nightwish on bass and vocals; he continued to perform and record with Tarot as well, releasing eight more studio albums including a re-recording of the band's debut, The Spell of Iron MMXI, in 2011.

He made his debut with Nightwish on the group's fourth studio LP, 2002's Century Child, and has appeared on every album since then. Despite being a full-time member of two active groups, Hietala has found time to lend his skills to countless other projects, frequently appearing on records by Dutch symphonic metal group Delain, and guesting on albums by Altaria, Amorphis, Charon, and Ayreon, just to name a few. As a producer, he has worked with both of his meal-ticket bands, as well as contemporaries like Warmath, Conquest, and Amorphis. In 2019 Hietala issued his debut solo album, Mustan Sydämen Rovio. An English version of the LP titled Pyre of the Black Heart was released the following year. ~ James Christopher Monger, Rovi