Inside a run-down shack on the banks of the Delaware River, married Philadelphia door-to-door salesman Joe Wilson lies dying in a cheap, blood-spattered suit, stabbed through the heart by an assailant he describes with his last breath as a mysterious veiled woman. So begins master detective Ellery Queen's strangest case ever. For Joe Wilson is not one man, but two, each married secretly to a different wife - and in his other life, as New York millionaire Joseph Kent Gimball, he has just changed the beneficiary of a million-dollar life insurance policy. With painstaking brilliance Ellery Queen sifts through a plethora of clues to solve the riddle of the Halfway House murder, beginning with the most important question of all: Whom did the murderer think she was killing, impoverished Wilson or millionaire Gimball? And why?