There are multiple artists with the name The Knife:
1) Electronic duo from Stockholm, Sweden.
2) Spanish symphonic prog band
The Knife was an electronic duo from Stockholm, Sweden formed in 1999. The band consisted of siblings Karin Dreijer Andersson (formerly of Honey is Cool, now Fever Ray) and Olof Dreijer - who also run their own record company, Rabid Records.
The group rarely made public appearances, most of their promotional photos featured the members wearing masks, and formerly refused to perform live concerts.