Hardcastle’s Traitors

Ison throws his readers more than a few curveballs in the 11th mystery featuring irascible Divisional Det. Insp. Ernest Hardcastle, of the Metropolitan Police (after 2012’s Hardcastle’s Frustration). On New Year’s Eve 1915, the DDI’s plans for celebrating are disrupted by the murder of jeweler and pawnbroker Reuben Gosling. A witness reports seeing two men speed off in a motorcar, but when the police locate the vehicle’s owner, wealthy Sinclair Villiers, he plausibly denies any involvement. Routine police work leads to the discovery that Sinclair’s army captain son, Haydn, who often borrows the car, spent the night of the crime with his colonel’s wife. Hardcastle, theorizing that an enemy of Haydn’s was trying to frame him, looks into an espionage angle, only to find British intelligence intervening in the case. Ison does little to distinguish Hardcastle from countless other gruff series leads, but he does offer readers a genuinely unusual secret at the heart of the mystery. (Nov.)