During a directors’ meeting of a decaying joinery business in the new town of Evingden, in Surrey, there is an explosion, which kills three of them. Experts say the offices were blown sky-high with blasting powder. “If you read about a thing like this in a novel, you’d say it was a bit overdone, wouldn’t you?” says Inspector Cromwell, who arrives from Scotland Yard with Superintendent Littlejohn to help the local police. Malcontents from the scruffy side of the new overspill population, an over-enthusiastic fire-raiser, or even a creditor driven off his head through worrying about his dues? It turns out not to be as simple as that. There are family feuds, matrimonial disasters, and angry discontented women mixed up in affairs of the Excelsior Joinery Company, and Littlejohn eventually finds a solution in a most unexpected quarter.