Demon formed in 1980 by vocalist Dave Hill and guitarist Mal Spooner, both hailing from Leek, Staffordshire. They drew their initial audience from the New Wave of British Heavy Metal movement in 1980.

The original lineup was completed by Les Hunt (rhythm guitar), Chris Ellis (bass) and John Wright (drums). The band were rapidly snapped up by Carrere Records to join their stable of metal bands. Their debut album Night of the Demon was released in 1981.

After their follow-up album The unexpected guest in 1982, the band experimented beyond the NWOBHM sound and third release The Plague (1983) was a full-blown concept album, which led them to adopt a consistent melodic hard rock style. With the decline of the NWOBHM as a major force, The Plague was their last album for Carrere and the following albums British Standard Approved (1984) and Heart of our time (1985) came out on a small independent label. Following the tragic death of Mal Spooner in 1985, Hill has single-handedly guided the band into the 21st century with a succession of well-received but little-known albums. They maintain a hardcore cult following throughout Europe.