From the Jacket: San Francisco is the locale of this fast-paced mystery by the author of The Indigo Necklace and The Man in Gray—San Francisco of the fabulously steep hills, the fog drifting in over the bay, the excellent restaurants and the exotic dives. On one of its hills, in a muffling fog, Pat and Jean Abbott, Mrs. Crane’s delightful sleuthing couple, see a car crash into a hydrant, and it's no surprise to anyone when a murdered man is found slumped behind the wheel. The dead man, however, is the estranged husband of a very good friend of the Abbotts, Nancy Leland. Because Nancy is suspected of the murder, the Abbotts are from then on involved in two more murders, mayhem and a few other slightly illegal activities. A grim chain of apparently unrelated clues leads them to the murderer, and to a solution of more than passing interest to the Federal Bureau of Narcotics.”