"A Chip in the Sugar" is one of the monologues from Alan Bennett's series titled "Talking Heads." In this story, we follow the character Graham, a middle-aged man who lives with his elderly mother. Graham's life is relatively uneventful and is marked by a routine and dependency on his mother. His world is upended when his mother reunites with an old flame, Mr. Turnbull.

Graham is initially disturbed by this development, as he feels his secure, predictable life with his mother is threatened. Mr. Turnbull's presence brings about significant changes in his mother's behavior and outlook, which Graham views negatively. He perceives Mr. Turnbull as a rival for his mother's affection and attention.

As the story unfolds, Graham discovers that Mr. Turnbull holds controversial political views, which he uses to sow discord between his mother and Mr. Turnbull. Eventually, it is revealed that Mr. Turnbull is not as perfect as Graham's mother thought, having hidden some details about his personal life, including a previous marriage that ended due to his infidelity.

Graham's mother decides to end her relationship with Mr. Turnbull, and the status quo of Graham's life with his mother is restored. However, the experience leaves Graham with a slightly altered view of his relationship with his mother, hinting at his underlying fears and dependency.

This story, like many in "Talking Heads," explores themes of loneliness, the complexity of human relationships, and the quiet desperation often found in ordinary lives. It provides a poignant, often humorous look at the fears and behaviors that dictate the course of one's life.