The Hard Detective’s cases (A Detective at Death’s Door, 2005, etc.) always try her strength, but this one may be the hardest yet.
A phone call brings terrorism shockingly close to Supt. Harriet Martens and her husband, John Piddock. One of their police-officer sons, Graham, has been killed by a London booby trap, and his twin, Malcolm, is hospitalized in a coma. Any other officer would be prostrate, but the Hard Detective, traumatized and grief-stricken, is back on the job at the Assistant Commissioner’s urging the following day, conducting a discreet one-woman investigation into the theft of CA 534, a souped-up herbicide that’s vanished from the office of Dr. Giles Lennox, Director of Heronsgate House Institute, before it can be destroyed. How potent is CA 534? If two drops of the oily stuff could defoliate a garden plot, Harriet can only imagine what a full test-tube could do. So as she’s struggling to cope with Graham’s death and Malcolm’s grave injuries, she’s asking how likely it is that Christopher Alexander, the Director’s assistant, leaked news of the secret project to either of the leading suspects, Christopher’s old academic mentor Prof. Ernst Wichmann, or the dotty but determined Women Against Genetic Interference.
The mystery is solved by a series of convenient, and conveniently delayed, recollections. It’s a testament to this series that the death of the heroine’s son produces a reaction that’s stronger but no more heartfelt than usual.