The Fantasticks is a riff on the Romeo and Juliet story, with a musical twist. The show is narrated by the character of El Gallo, who steps in and out of the story itself.
Two Fathers who live next door to one another have agreed that their children should marry. Knowing their children would never agree to a pre-arranged engagement, though, the Fathers have pretended to feud with each other. They've even built a "wall" (played by "The Mute," a dancer) to indicate that their children are never to meet.