Grease is a popular musical by Jim Jacobs and Warren Casey. A very successful film version was made in 1978 starring John Travolta and Olivia Newton-John. The musical is based around some of the subcultures of 1950s High school America, including the "tough guy" working-class greasers from which the musical takes its name. The musical takes place at fictional Rydell High in Chicago, Illinois. Some of the social issues featured in the musical are teenage pregnancy and gang violence; its themes include love, friendship, rebellion and sexual exploration during adolescence, and, to some degree, class consciousness/class conflict. The show originated in Chicago and made its premier at The Kingston Mines. The original production was over three hours long and had to be whittled down significantly in between its opening in Chicago and its premier on Broadway. When the show opened on Broadway in 1972, it was well received by the public despite less-than-favorable reviews from critics. Nevertheless, it was nominated for seven Tony Awards and the 1994 revival was nominated for three. In 2003, Grease was voted Best Musical of All-Time in a Channel 4 poll.