Did the son of Louis XVI and Marie Antoinette die during his imprisonment in the Temple Tower, or was he one of the people claiming to be the Lost Dauphin after the Terror ended? And was Kasper Hauser, the mysterious boy who claimed to have spent his entire childhood in a subterranean dungeon, really the Crown Prince of Baden, or was he suffering from pseudologia fantastica, a pathological desire to deceive other people? In this highly entertaining work covering the most famous unsolved cases of disputed identity, Jan Bondeson uncovers all the evidence, then applies his medical knowledge and logical thinking to ascertain true stories behind these fascinating histories.