This is a near-future police procedural tale, in which DCS Kat Frank of the Warwickshire force is assigned a cold case of missing persons. IN THE BLINK OF AN EYE two young students vanished from their respective homes, and the search was minimal as they were adults.   In a twist on Sherlock Holmes, a powerful computer called AIDE (Artificially Intelligent Detective Entity), Lock joins the team on a pilot programme to see if AI can be applied. Since it’s faster than people at searching documents and the web, using a computer makes sense. What Kat Frank can’t approve of is letting the computer make decisions.   I like that we follow a search for male students because all too often, women are the victims in crime stories. Warwickshire is a rural but active location, with large towns, colleges and a varied populace. The computer Lock is put to work scanning CCTV, where footage exists, and looking for links in social media, and it generates statistics instantly, like how many people go missing, and how they turn up if they do. Kat carries an interface for the computer around with her, like a smartwatch, and this can project an image of Lock as a man in a suit, to the surprise of many. We’re not told how much power the AI needs to use, or where the data centre feeding it is located. We concentrate on Kat’s experience as the person unwillingly walking around with this Spock-like presence at her fingertips.    Kat is a solo mum, since her husband passed away, doing her best to raise her teen son Cam. I’m not impressed by her parenting style which is still hovering, texting many times a day, swearing at the lad in person or text, and calling him ‘useless’ to his pals. No wonder, I feel, he’s keen to be elsewhere. Of course, that’s part of the story.   Chief Constable McLeish, while senior in outlook, is perhaps pragmatic about never getting enough resources to pay enough officers to keep up with an expanding crime rate. The police are also responding after the fact, which may not keep people safe. We see that the officers in the cold case review squad have personal circumstances that can cloud judgment, make them less fit and strong, and tire them. The AI keeps working without tiring. The author Jo Callaghan asks, in her first book, whether we want to give up privacy, empathy, and wise judgment in our unending need for speed.  IN THE BLINK OF AN EYE all our lives could be changed. This tension-filled crime story asks questions of the readers beyond the usual trail of clues and red herrings. Recommended for fans of mystery and science fiction.