The Spirit of Harmony Chorus will present pre-show entertainment under the Okoboji Summer Theatre awning at 7:30 pm, Friday, July 15 before the production of "An Inspector Calls." Suspense rules when a middle-class Yorkshire family meets the enigmatic Inspector Goole, in this English classic whodunit. Celebrating their recent regional first-place competition results, the Spirit of Harmony Chorus is excited to share their harmony with OST audiences again.