during the week , they never hung out , but they had those saturdays , and there was something to those days , whether they hung out in the backyard , or wandered through the gravel dumps off harvest street , or hopped the subways and rode downtown not to see anything , just to move through the dark tunnels and hear the rattle and brake-scream of the cars as they cornered the tracks and the lights flickered on and off that felt to sean like a held breath .