A Perfect Circle is an American rock band formed in Los Angeles, California in 1999 by guitarist Billy Howerdel and Tool vocalist Maynard James Keenan. A Perfect Circle released three of their four studio albums in the early 2000s: their debut Mer de Noms in 2000, a follow-up, Thirteenth Step in 2003; and an album of radically re-worked cover songs, Emotive, in 2004. https://en.wikipedia.org/wiki/A_Perfect_Circle