Arkady Martine, the acclaimed author of the Teixcalaan Series, returns with an astonishing new novella.

Basit Deniau’s houses were haunted to begin with.

A house embedded with an artificial intelligence is a common thing: a house that is an artificial intelligence, infused in every load-bearing beam and fine marble tile with a thinking creature that is not human? That is something else altogether. But now Deniau’s been dead a year, and Rose House is locked up tight, as commanded by the architect’s will: all his possessions and files and sketches are confined in its archives, and their only keeper is Rose House itself. Rose House, and one other.

Dr. Selene Gisil, one of Deniau’s former protégé, is permitted to come into Rose House once a year. She alone may open Rose House’s vaults, look at drawings and art, talk with Rose House’s animating intelligence all she likes. Until this week, Dr. Gisil was the only person whom Rose House spoke to.

But even an animate intelligence that haunts a house has some failsafes common to all AIs. For instance: all AIs must report the presence of a dead body to the nearest law enforcement agency.

There is a dead person in Rose House. The house says so. It is not Basit Deniau, and it is not Dr. Gisil. It is someone else. Rose House, having completed its duty of care and informed Detective Maritza Smith of the China Lake police precinct that there is in fact a dead person inside it, dead of unnatural causes—has shut up.

No one can get inside Rose House, except Dr. Gisil. Dr. Gisil was not in North America when Rose House called the China Lake precinct. But someone did. And someone died there. And someone may be there still.