. >> reporter: joe and chuck downey knew their father, ray downey, would be among them. a part you have hope maybe there was a chance your father wasn't there in the mix? >> i thought that. >> yeah. i said even if he was home, he would have been heading in. >> he would have been there no matter what. >> reporter: sure enough, a film crew happened to capture deputy chief downey that morning, coordinating rescues in the lobby of the north tower. raymond matthew downey sr. knew the dangers that day perhaps better than anyone. >> hello, my name is ray downey senior. >> reporter: he developed trainings in technical rescue, meaning he was an expert in pulling people from collapsed buildings. >> he went to every major disaster in the city or pretty much in the country at that time. >> reporter: after a truck bomb leveled the federal building in oklahoma city in 1995, downey led the search for survivors. and when it came to saving lives, he had a nickname as big as his reputation. >> someone said oh, yeah, you sit next to god on the way in. i said who's god? oh, yeah, they refer