Gnarls Barkley is an American neo soul duo, composed of music producer Brian Joseph Burton (known professionally as Danger Mouse) and singer-songwriter Thomas DeCarlo Callaway (known professionally as CeeLo Green). Their debut studio album St. Elsewhere, was released in 2006, along with its first single "Crazy". Both single and album were a major commercial success and have been noted for their large sales by download. The duo released their second album The Odd Couple in March 2008.