George Porter Dillman and Genevieve Masefield, used to the grand opulence of the Cunard cruise line, are at first disappointed with the Marmora, a small, unimpressive ship that's part of the P&O shipping line, the company that now employs them as ship's detectives. They know that they're certain to encounter the same petty thefts and confidence tricksters they're used to dealing with, though they hope identifying the culprits among the 500 or so passengers will prove a little easier than it does aboard the great 2,000 passenger Cunard ships.Their hope is misplaced, however, and they soon settle in to the routine of taking reports from agitated passengers and doing their best to recover whatever stolen jewelry or purloined cash the unfortunate travelers are missing. The cruise is certain to be unique in at least one respect, however: the Duke and Duchess of Fife, along with their two small children, are aboard, and the detectives' secondary task is to keep an eye on the royals and...

Temporarily forsaking the Cunard Line to work as private detectives aboard the Minnesota, a combination freighter and passenger ship owned by the Great Northern Steamship Company, George Porter Dillman and Genevieve Masefield are eagerly anticipating the prospect of a cruise bound for the Far East. Once aboard, the two begin to establish separate social circles in order to keep an eye on as many passengers and crew as possible. As the ship gets under way, it's smooth sailing, and George and Genevieve are hoping that perhaps this will be their first uneventful cruise. Unfortunately, their luck turns quickly as a fiery Catholic missionary is murdered in what proves to be the first in a series of crimes that will stretch them to their limit. Dillman and Genevieve have to use all their skills to combat danger on more then one front and to prevent an otherwise idyllic (and romantic) trip from becoming a terrifying nightmare.

George Dillman and Genevieve Masefield have to be on their mettle when the great J.P. Morgan sails to New York with them on the Oceanic, a vessel that belongs to a shipping line Morgan owns. The death of his bodyguard and the theft of priceless paintings from his stateroom throw everything into confusion.The presence on board of an unwanted suitor for Genevieve, and a mad Welsh artist with his wife and mistress in tow, complicate an already difficult situation. The only way to placate the infuriated J.P. Morgan is to solve the murder but time is limited and there are far too many suspects.

Genevieve Masefield and George Porter Dillman have met all kinds of people while sailing as ship detectives for the Cunard Line. But as they prepare to embark on yet another Atlantic crossing, this time aboard the famous Caronia, they encounter an entirely new circumstance: two men brandishing shotguns herd a man and a woman aboard ship in shackles, right in front of scores of baffled passengers.Curious, the two detectives come to find out that the young couple have been captured in New York by Scotland Yard and are being transported back to England to stand trial for murder. Before long, George and Genevieve have a chance to talk to the Scotland Yard officers, and come away far less than convinced that the captured couple are the vicious criminals they're thought to be.Of course, no matter how much they'd like to follow up on the hunch that the two may not be guilty, they've got a ship full of their standard responsibilities: purse-snatching passengers, stateroom burglars,...

September 1907. George Porter Dillman sets sail from Liverpool on the Lusitania's maiden voyage. Hired by the ship's captain to pose as a passenger, George is in fact a private detective for the Cunard Line. In the first days of his voyage, George only has to deal with a few petty crimes. But then an expensive piece of jewelry is reported stolen and a body is found. Working quickly to solve both crimes, George makes an unusual friend, Genevieve Masefield, and the two uncover secrets aboard the ship that prove explosive.

When they sail from New York on the Celtic, a White Star ship, George Dillman and Genevieve Masefield face an immediate problem. They are warned that a dangerous criminal may be aboard. Genevieve excites the interest of two passengers, a Briton and an American, who compete for her attention. Also on board is the creator of the most famous fictional detective of them all - Sherlock Holmes. Dillman is delighted to meet Sir Arthur Conan Doyle but the author is soon the victim of a crime when his annotated copy of A Study in Scarlet is stolen. More thefts follow.Sir Arthur and his wife attend a séance and Genevieve, though highly sceptical, also wishes to see the medium in action. The leisured luxury of first class is contrasted with the privations in steerage where some passengers are emigrants who were refused entry to America. One man is so distressed that he contemplates suicide. While the Celtic sails on, Dillman and Genevieve work frantically to solve the various crimes even...

Genevieve Masefield and George Porter Dillman make a living anonymously, cruising the seven seas aboard the early twentieth century's most extravagant sailing vessels as ship's detectives. In this line of work they've experienced more than their share of humanity. Along with the members of first class in all their finery, the card cheats and pickpockets plying their trade, the lascivious crew members and elderly cruise matrons that normally populate the voyages George and Genevieve work on, the Salsette boasts a group of travelers whose lives are set to intersect in ways none of them could have foreseen on dry land.There are a pair of British men, traveling independently, who clearly know each other from another place and time; though each tries to hide it, there is no love lost between them. There's an elderly Indian man whose powers of deduction may be based on more earthly techniques than the mystical energy he claims to possess. Not to mention a young woman and her...

November 1907. Only a few short months after crossing the Atlantic aboard the Lusitania, George Porter Dillman and Genevieve Masefield sail from Liverpool on the maiden voyage of the Mauretania. Posing as passengers, Dillman and Genevieve endure a nightmare voyage during which severe weather batters the vessel unmercifully and keeps the passengers away from the decks. Dillman is instrumental in rescuing a crew member from being washed overboard but he is too late to save one of the First Class passengers from the same fate. At first, it looks like a case of death by misadventure. But Dillman and Genevieve come to realize that it was an act of calculated murder, connected with the presence on board of a record shipment of gold bullion - twelve tons in all - sent from the Bank of England.