Wiki Coffin, linguist aboard the U.S. Exploring Expedition, the famous voyage meant to put America at the forefront of 19th century scientific discovery, brings many skills to his job. Whether he's translating native languages, assisting his good friend Captain George Rochester as unofficial first mate, or upholding the rule of law as deputy to the sheriff of the port of Virginia, Wiki is never far from the action aboard the seven ships that make up the expedition.

But when they encounter a wrecked sealing ship and its desperate crew on the shoals of remote, uninhabited Shark Island, Wiki has little idea just how many of his skills are about to be put to the test. As soon as they board the wreck, a dead body turns up with a dagger firmly inserted between its shoulder blades. And it's not just any dead body: the victim of the brutal murder is none other than the enigmatic captain of the doomed voyage. What's more, Wiki's colleague and nemesis Lieutenant Forsythe is suspected of the crime.

Knowing full well that Forsythe is capable of such violence, Wiki nonetheless believes him innocent and is duty-bound to prove it for the good of the expedition. Was the murder a case of mutinous sealers taking the law into their own hands? Did the secrets of several mysterious long-ago voyages finally come back to haunt a dishonest and dishonorable captain? Or is Shark Island home to something more sinister than a few lonely goats? Something isn't quite right about the crew of the wrecked ship, and Wiki will stop at nothing to find out just what it is that they're hiding, and, in the process, unmask a vicious killer.