the sirens aren't going. >> frightened customers huddle in terror inside a dark refrigerated storeroom. >> jesus! [ people screaming ] [ wind blowing ] >> jesus, jesus, jesus. heavenly father -- >> everybody okay?! >> you guys all okay? >> yes! >> we're all right! we're all right! >> amazingly, everyone inside survives. >> i've got debris on the ground, right here! debris on the ground! >> the massive tornado, believed to be three quarters of a mile wide with winds exceeding 190 miles an hour rips a path of destruction four miles long, right through the heart of the city. >> oh, my god! >> by monday morning, the devastation was clear. buildings on fire. entire neighborhoods wiped out.