The author uses the fire scene to show a new side of Johnny by instead of Johnny acting like his usual, frightened self, he seems more alive because of the thrill,This is shown where in the text it states “He looked over his shoulder and saw that the door was blocked by flames, then pushed open the window and tossed out the nearest kid. I caught one quick look at his face; it was red marked from falling embers and sweat streaked, but he grinned at me. He wasn't scared either. That was the only time I can think of when I saw him without that defeated, suspicious look in his eyes. He looked like he was having the time of his life.”This is explaining that Johnny is sort of like a whole new person because of the life or death situation that they’re in.