First a murder, then an explosion. Thousands run for their lives as suburbs around the London docks are flattened. Might be a cliche to say Devil's Porridge starts with a bang, but as much of the action is set near a munitions factory, I feel I can get away with it. In the aftermath of the blast, a disparate group of characters make their way north to Gretna near the English-Scottish border. Irishmen and women who harbour disdain for their English overlords, a shy London girl who needs work, a Belgian refugee and a troupe of 'lady police' will rub up against each other as the story unfolds. The sheer size of the munitions complex at Gretna reminds us that World War I was warfare on an industrial scale. Young women -- munitionettes -- carried out the dangerous work and 'lady police' were there to keep an eye on their moral as well as physical safety. The task of solving two murders and thwarting an assasination falls to one of the 'lady police', Kirsty Campbell, an engaging and resourceful heroine. Fascinating historical insights give texture to Longmuir's cracking tale of espionage, rebellion and misplaced loyalties.

For me, one of the defining features of Chris Longmuir's style is her skill at introducing dark, shocking elements into the everyday without over-writing them. They occur naturally, even simply, in what seems an artless, throwaway manner and have all the more impact as a result. The various evils perpetrated in this book are typical of that technique. Despite the fact that the action is set in and around munitions factories, the most explosive passages concern the actions and fates of individuals. In an instant, characters who seem to be charming, even loving, are capable of the most brutal sociopathic deeds. Victims are disposed of dispassionately and yet the perpetrator subsequently regrets his actions. It all makes the sinister events even darker. The book is a masterful recreation of the historical period in which it’s set, and the threads of Irish rebellion, German spying, gender politics are woven into a complex background against which the cast of characters live their ‘ordinary’ lives, form friendships, fall in love, and suppress or indulge their passions. I’d like to have seen more of Kirsty Campbell. She’s clearly at the centre of the book and, of course, an entire series is being built around her, but here, the focus has necessarily to be shared between many different characters. That’s not a criticism, however, it’s a recognition that she’s a woman who’s bringing a new dimension to the historical police procedural.