French Strikes Oil

French Strikes Oil is a 1951 detective novel by the Irish-born writer Freeman Wills Crofts. It is the twenty eighth and penultimate entry in his series of novels featuring Inspector French, a Scotland Yard detective of the Golden Age known for his methodical technique. It was published in the United States by Dodd Mead under the alternative title of Dark Journey.
No further French novel appeared for six years after this, although he featured in a short story collection The Mystery of the Sleeping Car Express published in 1956.

Synopsis

French, now promoted to Superintendent, is called in to investigate the murder of Maurice Vale. Oil had recently been discovered on the family estate which promised to make them very wealthy. While Rodney Vale was keen to exploit the valuable new resources, his brother Maurice was strongly opposed due to the damage to the picturesque countryside. Maurice's death therefore potentially benefits several of his relatives. Curiously, French discovers two separate gloves by the body, one belonging to a man and one to a woman.