Finnforest was a trio of Pekka Tegelman, Jussi Tegelman and Jukka Rissanen when they released their first album in 1975. Rissanen left the group soon after the first album because he went to study classical music in Hungary. Finnforest's second album was recorded in 1976 using some session musicians because the band consisted only of the Tegelman twins at the time.
In 1978 Finnforest was back with a new lineup: Jussi Tegelman, Pekka Tegelman, Jarmo Rissanen (guitar), Jarmo Savolainen (keyboards), Heikki Keskinen (tenor saxophone) and Tuomo Helin (bass). This was the lineup on the band's third album "Demonnights" which was also their last.