Clarke’s novel is composed of journal entries written in the first-person by a triple-named narrator. He is called The Beloved Child of the House, Piranesi, and Matthew Rose Sorensen at different points in the book. Each entry begins with a title and date; there are six entries in Part 1.

The first entry’s title is also the first line of the entry and is dated “Entry for the First Day of the Fifth Month in the Year the Albatross Came to the South-Western Halls” (all dates are written in small capital letters). Currently unnamed, the narrator describes statues in the hall and three tides rising in the flooded labyrinth. A prayer to the house and climbing statues protect him from the tides.

In the second entry, dated the 7th day of the same month, the narrator travels through halls and doorways, cataloging statues. He uses proper nouns for architectural details and natural elements. The “House” has three levels: one submerged by the “Tides,” one level in the “Clouds,” and the middle level where birds and people can exist. The protagonist sees the Other (who is later named as Valentine Ketterley)—the only other living person he has knowledge of at this point.