Chapter 15: AXIOM Speaks Out of Turn

The case interface terminal at Southwark Precinct occupied a narrow room on the second floor that had been, in an earlier institutional life, a photographic darkroom. Someone had stripped the chemical sinks and the ventilation baffles but left the absence of windows, so the only light came from overhead strips that had been calibrated to AXIOM's preferred working spectrum: a clean, slightly bluish white that made every surface look like evidence. Holmes had commandeered the room two weeks into the investigation on the grounds that it had no integrated sensor array beyond the terminal itself, which was the closest approximation to privacy the building offered. She used it on Tuesday and Friday mornings. I had been attending since the third week.

The terminal was a standard Met-issue interface unit, matte black chassis, holographic projection field extending approximately a metre and a half in each direction from the central display column. When AXIOM was active, the field emitted the blue-white glow that I had come to think of — unreasonably, I knew, but persistently — as the system's version of a cleared throat. A way of indicating presence without announcing intention.

I had, by that point, been timing AXIOM's response latency for nineteen days.