Storefront Theater Musical revolves around the Upstage Theater, a small storefront theater, which is being shut down by the city unless they fix the code violations.

The Upstage Theater is shared by three theater companies, Picasso's Missing Ear, The Really Realistic Realism Theater company, and L'eggs in a Basket, who don't get along, but in order to save the theater they need to work together and hold a benefit to raise funds to fix the violations.