"In this, the third of the series, Dr. Jeremy Janes, the Flying Doctor, moves to the north coast of Australia on a call which takes him into the pearling area. This involves him in a medical crisis when he himself discovers the perils of donning a diving suit to examine the foot of a pearl diver which has been caught in a giant clam. He also becomes involved in an intrigue in which a man who has discovered how to produce cultured pearls in tropical waters is threatened by jealous competitors." -- Dust jacket