Vocalist, pianist, composer, and poet Diamanda Galás has a three-octave range, which she applies to experimental compositions that vary from goth to electronica to opera and into territories hitherto only charted by the out-there composers like Frank Zappa and Laurie Anderson. Her dark, dramatic looks and occult themes in albums like her 1982 debut Litanies of Satan have caused some to accuse her of satanism.

Galás came to international attention for her late '80s three-part "plague mass" concerning the AIDS epidemic as -- in her view -- referenced in the Bible, in particular Psalms and Leviticus. After Galás performed the first installment of her mass, The Masque of the Red Death, in Italy, the Italian government denounced her as a heretic.

Galás has also been involved in AIDS awareness campaigns, activism, and support groups, having lost a brother and close friend to the epidemic. Her songs have been heard in movie soundtracks such as Bram Stoker's Dracula and Natural Born Killers.

Her album Gulity! Guilty! Guilty! was released in 2008. She returned to San Diego in January 2011, to speak at UCSD’s Sonic Diasporas Alumni Festival.

In 2017, Galás released an album of traditional and jazz standards, All the Way, as well as a live album, At Saint Thomas the Apostle Harlem.

In August 2022, Galás released her album Broken Gargoyles via Intravenal Sound Operations. The title refers to WW1 soldiers who were so facially disfigured they were called “broken gargoyles." The first incarnation of the work was played as a sound installation at the Kapellen Leprosarium (Leper's Sanctuary) in Hanover, Germany, built around 1250 and once used to quarantine those who suffered from the plague and leprosy in the Middle Ages.