Twenty-five years before the setting of the opera, Iolanthe, a fairy, had committed the capital offence of marrying a mortal. The Queen of the Fairies had commuted the sentence to lifelong exile, on condition that Iolanthe left her husband and never saw him again.
Her son, Strephon, has grown up as a shepherd, half fairy, half mortal. Strephon loves Phyllis, who is a Ward of the Court of Chancery. She loves Strephon, but is unaware of his mixed origin. Meanwhile, the entire House of Lords is enamoured of Phyllis, especially the Lord Chancellor, her guardian.
At the start of the opera, the fairies persuade the Queen to pardon Iolanthe, and she returns, introducing Strephon to her sisters. The Queen agrees to help when Strephon announces that he wishes to marry Phyllis, despite the Lord Chancellor's refusal.
The House of Lords enter, and appeal to the Lord Chancellor to give her to whichever peer she chooses. Phyllis herself enters, and declines to marry a peer, announcing her intention to marry Strephon. The peers angrily refuse, and leave. taking Phyllis with them. Iolanthe enters and holds a tender conversation with her son. But, as she (like all fairies) looks like a girl of seventeen, Phyllis and the peers misinterpret the scene. They don't believe that Strephon is being faithful, and Phyllis decides to marry one of two peers, Mountararat or Tolloller.
The fairies take revenge by sending Strephon to Parliament, and casting a spell to make all the peers pass any bills that Strephon chooses, including entry depending on intelligence rather than class. The peers are terrified, and appeal to the fairies not to carry this out, but they refuse, so all angrily spurn each other.
The peers are upset about Strephon's success in Parliament, and appeal for the fairies to return things to normal. One of the lords sings in explanation. The fairies would like to oblige, as they have fallen in love with the peers themselves, but it is too late to stop Strephon. The Queen is shocked by the fairies' feminine weakness, and while acknowledging the effect on her, of a nearby sentry, asserts that she remains strong.
Tolloller and Mountararat discover that if either marries Phyllis, then by family tradition, they must duel to the death. Both then renounce Phyllis in the name of friendship. Meanwhile, the Lord Chancellor has had a sleepless night, and eventually decides to marry Phyllis himself.
Strephon confesses to Phyllis that he is half a fairy, and they decide to marry as soon as possible. They persuade Iolanthe to appeal to the Lord Chancellor on their behalf, and she does so, revealing that she is his wife.
Thus, she again incurs the death penalty. Meanwhile, the other fairies have married the other peers, and so all should die. The Lord Chancellor suggests that by adding the word 'not' to the fairy law, the fairies would not have to die. To save her life, the Queen marrys Private Willis, all the mortals are transformed into fairies, and they all fly away to Fairyland, leaving the House of Lords to be filled according to intelligence not birth.
Although the book on which Guys and Dolls is based was written by Jo Swerling and Abe Burrows the original story was written by one of the most elusive figures in popular literature, Damon Runyon. He was a small-town boy born in Manhattan, Kansas in 1880 and was the son of an itinerant drunkard, gambler and printer. As Runyon spent most of his life in the wake of hoods and hoodlums it is hardly surprising that most of the characters in "Guys and Dolls" were drawn from life. Indeed it was said that the reason Runyon had so many contradictions in his life was that he turned a blind eye to some of the immoralities of his friends and acquaintances which was born of an artistic need. In other words without associating with the underworld where would his fictional raw material come from and above all where would he find his characters? One of Runyon's comments when writing his stories was "To hell with plots, because nobody remembers much about the plots of Dickens and Mark Twain, they remember the chracters." Whether Dickens or Twain would have agreed with this comment is another matter!!
The main two male characters in "Guys and Dolls" were almost certainly based on two real-life people. Sky Masterson was drawn from the life of Bat Masterson a one-time sheriff of Dodge City and Nathan Detroit owes his character to the colourful gambler and cabaret partner of Jimmy Durante, Loy Clayton. Angie the Ox and Harry the Horse we also based on two real life gangsters. It is less clear where Sarah Brown originated, but is has been suggested that Miss Adelaide was derived from a friend of Runyon's call Miss Cutie Singleton who apparently had her wedding postponed several times due to her fiance always blowing the money for the ring on gambling!
Runyon never knew that "Guys and Dolls" became a musical as he died in 1946. It was not until 1948 that Feur and Martin tried to produce the show after engaging two librettists named Swerling and Burrows. The original libretto was not entirely a success and it was only when Frank Loesser became involved by writng the that the show was actually completed as Loesser had virtually done the libretto himself by the very nature of the songs. In 1955 "Guys and Dolls" was made into a film starring Marlon Brando, Jean Simmons, Frank Sinatra and Vivian Blaine. It remainsever-popular today and does not seem to date unlike other shows of this kind. The songs range from ballads such as "I'll know " to the fast and exciting "Luck be a Lady tonight" with the delightful songs by the adenoidal Miss Adelaide tucked in between. Perhaps it is this blend of music blended with Runyon's real-life characters that gives "Guys and Dolls" its special magic.