Crystal Castles are an experimental electronic band formed in 2003 in Toronto, Ontario by songwriter/producer Ethan Kath. Crystal Castles are known for their chaotic live shows and lo-fi melancholic homemade productions. They released many limited vinyl singles between 2006 and 2007 before releasing a trilogy of critically acclaimed albums between 2008 and 2012.

In 2005 Ethan Kath released the digital singles "Magic Spells" and "Untrust Us" under the moniker Crystal Castles. As they grew popular online he began receiving offers from record labels. In 2006 Kath recruited vocalist Alice Glass for the band's first physical four-track EP "Alice Practice" which was released on vinyl. Their debut album, Crystal Castles, was released in 2008 and was listed on NME's "Top 100 Greatest Albums of the Decade" list at No. 39. In 2010 their second album, titled (II), charted on the Billboard 200, and includes their first worldwide charting single, "Not In Love", featuring vocalist Robert Smith of The Cure.

Their third album, (III), was released on November 12, 2012 and was the number 1 album of 2012 on Tumblr and also on Hype Machine. The album included 4 singles: "Plague", "Wrath of God", "Sad Eyes" and "Affection". Glass announced her departure from the band in October 2014, citing personal and professional reasons. In April 2015, Ethan Kath released a new Crystal Castles track, "Frail", featuring a new singer, Edith Frances. He also announced they are writing and recording a new album.