From Benford's Gilbert and Sullivan Lexicon:
Having shown what could be done with Trial by Jury, Carte found financial backers and organized the Comedy Opera Company to pursue his dream of English musical theater. He then contracted with Gilbert and Sullivan to write their first full-length comic opera: The Sorcerer, which opened at London’s Opera Comique on November 17, 1877. The opera was at least moderately successful and ran for 178 performances.
The Sorcerer is historically significant in that it set the pattern and style that made the succeeding operas so successful. Gilbert’s control over the acting company and his firm insistence on disciplined teamwork were innovations that were then badly needed in British theater. He also brought into the company such stalwart performers as George Grossmith, Rutland Barrington, and Richard Temple. These performers (and soon others) stayed with the company for many years, and Gilbert and Sullivan obligingly wrote many roles specifically to suit their talents.
The Sorcerer’s plot involves an engaged couple who want everyone to be as happy as they, and so the groom-to-be brings in a “family sorcerer” to administer a love potion to the entire village. As you might expect, the love potion works, but everyone falls in love with the wrong partner. All is made right in the end, however, as the sorcerer breaks the spell by the expedient of giving himself up to the powers of evil –– in an appropriate puff of smoke. (You will soon learn that the Gilbert and Sullivan operas do not hinge on strongly convincing conclusions.)