In 1717, scholarly naval physician Sebastian Seaforth is press-ganged onto the pirate ship Grey's Lady. Torn between the dictates of his Hippocratic Oath and his disgust at the pirates' brutality, Seaforth serves his new crew reluctantly while awaiting his chance to escape. Things change the day the Grey's Lady is attacked by bloodthirsty monsters straight out of legend. The pirates call them sea-witches, but Dr. Seaforth knows them by another name. An adventure steeped in historical seafaring and medicine, with a hint of romance.