“One of the greatest riddles in Golden Age detective fiction . . . the unbridled ingenuity of its central puzzle has never been surpassed” (Kirkus Reviews). Mandarin Press is a premier publishing house for foreign literature, but to those at the top of this enterprise, there is little more beautiful than a rare stamp. As Donald Kirk, publisher and philatelist, prepares his office for a banquet, an unfamiliar man comes to call. No one recognizes him, but Kirk’s staff is used to strange characters visiting their boss, so Kirk’s secretary asks him to wait in the anteroom. Within an hour, the mysterious visitor is dead on the floor, head bashed in with a fireplace poker, and everything in the anteroom has been quite literally turned upside down. The rug is backwards; the furniture is backwards; even the dead man’s clothes have been put on front-to-back. As debonair detective Ellery Queen pries into the secrets of Mandarin Press, every clue he finds is topsy-turvy. The great sleuth must tread lightly, for walking backwards is a surefire way to step off a cliff.