Black Coffee was written as a play by Agatha Christie in 1930 and novelized as a mystery by Charles Osborne in the late 1990's. The story is set in the library of Sir Claud Amory's home in Abbots Cleve about 25 miles from London. Hercule Poirot is requested to come because Sir Amory who is a well known physicist believes that someone in his household is trying to steal a formula that is vital to the defense of England. Poirot and Captain Hastings hurry to Abbots Cleve to find Sir Claud dead and the formula is missing. It is reminder of another time and place and the many enjoyable stories by Christie.