For a brief spell during the mid-'80s, the heavy metal quintet Dio was one of the top U.S. concert attractions, boasting one of the most over-the-top stage acts of its time loaded with props and special effects (lasers, explosions, a giant dragon, etc.). The group's leader was singer Ronnie James Dio, who had previously become acquainted with the metal masses as the frontman of Ritchie Blackmore's Rainbow from 1975-1978 and Black Sabbath from 1979-1982.