Killswitch Engage is an American metalcore band from Westfield, Massachusetts, formed in 1999 after the disbanding of Overcast and Aftershock. Killswitch Engage's current lineup consists of vocalist Jesse Leach, guitarists Joel Stroetzel and Adam Dutkiewicz, bassist Mike D'Antonio, and drummer Justin Foley. The band has released eight studio albums and three live performance albums. Their eighth studio album, Atonement, was released on August 16, 2019.

Metalcore is a fusion genre combining elements of extreme metal and hardcore punk, that originated in the late 1980s. Metalcore is noted for its use of breakdowns, which are slow, intense passages conducive to moshing, while other defining instrumentation includes heavy guitar riffs often utilizing percussive pedal tones and double bass drumming. Vocalists in the genre typically perform screaming, more popular bands often combine this with the use of standard singing, usually during the bridge or chorus of a song. However, the death growl is also a popular technique within the genre.