Zwan was an American alternative rock supergroup formed by Billy Corgan and Jimmy Chamberlin, lead singer and guitarist, and the drummer of the Smashing Pumpkins respectively. The band released their only album, Mary Star of the Sea, in 2003 before disbanding acrimoniously during their world tour. Despite allusions to more material written by band members, no further material has surfaced beyond their studio album.
Other members included Paz Lenchantin on bass (from A Perfect Circle) and guitarists David Pajo and Matt Sweeney from various prior bands. Following the breakup, Corgan released a solo album before reforming the Smashing Pumpkins in 2005 with Chamberlin joining in 2006.
In 2017, Corgan briefly toured revisiting Zwan's material but none of the other band members have performed any of it outside of that tour.