The protagonist spends a routine day working at the office where his boss inquires casually about his mother's age. After a midday break marked by a sudden, chaotic run to catch a moving cargo truck alongside his colleague Emmanuel, he returns to work for the afternoon. Later, he walks home slowly along the quays, enjoying the green evening sky, and returns to his apartment building where he encounters his neighbors.
Upon entering the dark stairwell, he crosses paths with old Salamano and his mangy, mistreated spaniel who have endured years of a miserable, antagonistic routine together. Shortly after, he meets his other neighbor, Raymond Sintès, a warehouseman rumored to live off women. Raymond invites him into his messy room to share food and wine, eagerly recounting a violent physical altercation he had with the brother of his former Moorish mistress whom he accuses of deception.
Raymond explains that he beat the woman severely because she cheated on him and refused to work, but he wants to punish her further by humiliating her. He asks the protagonist to write a vindictive letter designed to lure her back so he can exact his final revenge. Indifferent yet accommodating, the protagonist drafts the letter to please his neighbor, officially sealing their new friendship over the shared task before returning to his quiet, dark apartment.