#Pyromania40 Facts for 40 Years! | Who are The Leppardettes? Several secret guest artists performed background vocals on Pyromania credited as "The Leppardettes": Terry Wilson-Slesser (Back Street Crawler), Rocky Newton (Lionheart), Pete Overend Watts (Mott the Hoople), Chris Thompson (Manfred Mann's Earth Band), and producer Mutt Lange.