Megadeth is an American thrash metal band formed in Los Angeles in 1983 by vocalist/guitarist Dave Mustaine. Known for their technically complex guitar work and musicianship, Megadeth is one of the "big four" of American thrash metal along with Metallica, Anthrax, and Slayer, responsible for the genre's development and popularization. Their music features complex arrangements and fast rhythm sections, dual lead guitars, and lyrical themes of war, politics, religion, death, and personal relationships.
In 1985, Megadeth released their debut album, Killing Is My Business... and Business Is Good!, on the independent record label Combat Records, to moderate success. It caught the attention of bigger labels, which led to Megadeth signing with Capitol Records. Their first major-label album, Peace Sells... but Who's Buying?, was released in 1986 and was a major hit with the underground metal scene. Band members' substance abuse issues and personal disputes had brought Megadeth negative publicity during the late 1980s. Nonetheless, the band went on to release a number of platinum-selling albums, including So Far, So Good... So What!, Rust in Peace, and Countdown to Extinction.