from www.aftersabbath.com :-
Jan Hollestelle cut his teeth as a bass player in Hilversum's beat combo "The Torero's" with his guitarist brother Hans Hollestelle. The brothers both played on the Dutch production of the musical Hair. They were in a few other groups together, including The Tower, and a fusion band called Spin. Jan recorded an instrumental single called 'Creepy' in 1973 and here it is. From 1971 he became a highly-demanded session musician and also works on classical compositions.