The Scottish progressive rock band from Glasgow named themselves after a play called „The Beggar's Opera“ by the English poet John Gay from 1728. They formed in 1969 and signed a record deal with the progressive Vertigo label in 1970. Waters Of Change was their second album, released in October 1971 and recorded with the following line-up: Ricky Gardiner (g, voc), Martin Griffiths (voc, cowbell), Alan Park (org, p), Gordon Sellar (b, g, voc), who replaced Marshall Erskine, Raymond Wilson (dr) and Virginia Scott (mellotron, voc), who joined the band as the sixth member. While their previous album featured symphonic prog with classical arrangements, the follow-up was based entirely on the band's own songwriting. Impressive mellotron arrangements by Virginia Scott and Alan Park's virtuoso keyboard playing, together with melodic guitar passages by Ricky Gardiner and Martin Griffiths' distinctive tenor, resulted in keyboard-heavy progressive soundscapes with occasional psychedelic rock elements.

Despite numerous live performances at home and abroad and many positive reviews from fans and critics, they never made it into the premier league of progressive rock. After two more albums, they disbanded in 1975. Waters Of Change is widely regarded as their best work and, as an original UK Vertigo release, is sought after not only by lovers of early British prog rock.