The song is sung by the spirit of Judas Iscariot (who had committed suicide earlier in the show). Judas asks Jesus a series of questions, such as why Jesus chose to come to Israel in 4 BC when it had no "mass communication" as opposed to modern times, whether Jesus had planned his own death, whether Jesus knew beforehand that his death would become famous, and whether Buddha and Muhammad were his equals. It is dominated by Judas repeatedly apologizing for asking questions ("Don't you get me wrong", "I only want to know"). Jesus does not respond to any of the questions.

Superstar was released as a single in 1969, before the album was completed. Sung by Murray Head with the Trinidad Singers, it initially debuted on the U.S. Billboard Hot 100 singles chart for the week ending 31 January 1970, eventually peaking at No. 74 in late February 1970. Nearly one year later, the single then re-entered the Hot 100 chart for the week ending 2 January 1971, eventually peaking at No. 60 on the chart in early March 1971. The single then fell off the chart three weeks later, but then almost immediately re-entered the Hot 100 chart a third and final time for the week ending 10 April 1971. It then rapidly climbed the Hot 100 chart during its third chart run, eventually spending two consecutive weeks at its peak position of No. 14 in late May and early June 1971. It performed even better in Canada, where it peaked on the Canadian RPM Top Singles chart at No. 6, its highest known position worldwide. A video of the song was released to promote the album, with Murray Head and the Trinidad Singers appearing.

In order to get the concept album of Jesus Christ Superstar off the ground, Decca/MCA first gave Andrew Lloyd Webber and Tim Rice money to make the single and begin the album. They wanted to release the single first, which caused uproar within the MCA board at the time.

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