Formed by Tool vocalist Maynard James Keenan and former Tool guitar tech Billy Howerdel, A Perfect Circle is an extension of the alt-metal-fused-with-art rock style popularized by Tool in the early to mid-'90s. Howerdel, who had been composing songs for years, as well as working with bands such as the Smashing Pumpkins and Nine Inch Nails, is the band's chief songwriter and producer. A Perfect Circle released their debut album, Mer de Noms, in 2000. Thirteenth Step followed in 2003, and the covers album Emotive appeared in 2004. ~ Tracy Frey