Artificial intelligence is enjoying a moment, so much so that there’s already a backlash claiming the market fervor is overblown and investors are headed for a disappointment. It’s no surprise, then, that mystery writer Jo Callaghan has come out with a character named Lock, an artificially intelligent detecting entity, or AIDE. It is partnered with Kat Frank, a very human P.I. who tends to rely on instinct, setting her up in opposition to a being that relies solely on algorithms.

In Leave No Trace, Kat and Lock pursue their first real case, which involves a complex plot of crucifixion and mutilation. It was preceded by In the Blink of an Eye, which saw the two detectives exploring cold cases. (A third book, Human Remains, is not yet available in this country but is promised for 2026.) The setting for the series is Warwickshire, near Birmingham in the English Midlands; AIDE Lock was developed by Professor Okonedo, a scientist at the National Institute for AI Research at Warwick University, who’s embarking on a pilot project with the local police.

The tension between the instinctive Kat and an algorithmic Lock reflects the real-life quandary of AI. How human is it? And what does that even mean?

The mysteries’ plots are standardly British, with all their distinctions among detective inspectors, detective sergeants, and detective chief superintendents. But there’s sufficient blood and gore to keep everyone happy. What makes Callaghan’s books unique is their focus on AI’s strangeness, as experienced by humans. It emerges that Professor Okonedo is Black and so chooses a Black model for the holographic “detective” projected from a band around Kat’s wrist. Of course, holograms can take many forms, and another option is the visage of a middle-aged white male detective.

It’s all very engaging for readers (and speaking of reading, the AIDE is alarmingly accurate in its ability to race through multiple documents or books in a matter of seconds). But it’s the built-in tension between the experienced investigator and her non-human partner that drives the series’ action.

Darrell Delamaide is the author of two novels, as well as two nonfiction books.