This is vintage Leo Bruce, enhanced by the effortless humour that is a hallmark of all his mysteries. This time, Carolus Deene is enjoying himself on a holiday cruise. On the first night aboard the Summer Queen, there is a shout of "Man Overboard!" From that point on to the moment of Deene's unexpected revelations, the reader will find that unique mixture of artless fun and grim terror Bruce devotees savour.