Mortal Sin is a thrash metal band that formed in 1985. The group formed around singer Mat Maurer and drummer Wayne Campbell in Sydney, Australia. At first Campbell had attempted to get Maurer into another band called Wizzard but the rest of that band was reluctant to support the idea so the pair struck out on their own, quickly recruiting Wizzard's guitar Keith Krstin, bass player Andy Eftichiou from a band called Judge and a second guitarist Neville Reynolds. Reynolds was fired for not being available to play at the band's very first show and was replaced by Paul Carwana.