In the historical novel series Masters of Rome, Colleen McCullough presents an unflattering depiction of Cicero's career, showing him struggling with an inferiority complex and Vanity, morally flexible and fatally indiscreet, while his rival Julius Caesar is shown in a more approving light. Cicero is portrayed as a hero in the novel A Pillar of Iron by Taylor Caldwell (1965). Robert Harris' novels Imperium, Lustrum (published under the name Conspirata in the United States) and Dictator is the three-part novel series based upon the life of Cicero. In these novels Cicero's character is depicted in a more balanced way than in those of McCullough, with his positive traits equaling or outweighing his weaknesses (while conversely Caesar is depicted as more sinister than in McCullough). Cicero is a major recurring character in the Roma Sub Rosa series of mystery novels by Steven Saylor. He also appears several times as a peripheral character in John Maddox Roberts' SPQR series. The protagonist, Decius Metellus, admires Cicero for his erudition, but is disappointed by his lack of real opposition to Caesar, as well as puzzled by his relentless fawning on the Optimates, who secretly despise Cicero as a parvenu.