"Axolotl" opens with a blunt summary of its own plot: "There was a time when I thought a great deal about the axolotls I went to see them in the aquarium at the Jardin des Plantes and stayed for hours watching them, observing their immobility, their faint movements. Now I am an axolotl." An axolotl, the narrator later explains, is the larval stage of a type of salamander.

The rest of the story recounts how this fantastic transformation took place. The narrator, a man living in Paris, has grown bored with the lions and panthers he usually observes at the zoo, the Jardin des Plantes. He decides to explore the aquarium and unexpectedly "hits it off with the axolotls." A sign above the tank tells him they are Mexican, but he already knows this because their pink faces remind him of Aztecs. He begins to visit...