Two school friends - Rosario and Milagros - reunite after many years. They take jobs working the night shift as street cleaners and although Rosario finds the job depressing, Milagros gets some amusement from the situation. Rosario is having an unsatisfying affair with garbage collector Morsa and looking after her increasingly senile mother. The story unfolds between three timeframes and the two women form a strong friendship, with the gruff Morsa a counterpoint to the nuances in the characters that emerge throughout.