Shadow King was a hard rock supergroup. Formed by former Foreigner lead singer Lou Gramm, former Sweet Savage, Dio, Whitesnake, Riverdogs, (currently Def Leppard) guitarist Vivian Campbell, Lou Gramm's former Black Sheep and then future Foreigner bandmate bass player Bruce Turgon, and drummer Kevin Valentine.
Vivian Campbell and Bruce Turgon both also played with Lou Gramm as a solo artist previous to Shadow King, with Vivian playing on Long Hard Look, and Bruce playing on Ready or Not and Long Hard Look.
They released a self-titled album in 1991. Although plans were made for a tour, they performed only once, at the Astoria Theatre in London, England, on December 13, 1991. Shortly afterward, Vivian Campbell announced he was leaving Shadow King to join Def Leppard. Although replacements were considered, the band members eventually went their separate ways, with Gramm and Turgon rejoining Foreigner in 1992.