ISBN 0-00-651259-3 - HarperCollins, 1968
Once again, Troy Alleyn is 'in situ' when a crime takes place. This time, a gang of international crooks is involved in forgery, robbery and murder. But which one of the river cruise boat Zodiac's passengers is the notorious ringleader nicknamed the 'Jampot'?
As is frequently the case in her mystery novels, Ngaio Marsh displays her interest and expertise in the art world.