In 64 AD, Rome was the most magnificent city in the world. Fourteen sprawling districts were home to some two million people. But underneath the glorious façade, trouble was brewing. Rome’s erratic, ruthless ruler, Nero, was known for his decadent lifestyle and violent behavior. At the age of 16, he rose to power following the murder of his stepfather, Claudius. There were rumors that he murdered his mother and kicked his pregnant wife to death. Against the will of the senate, Nero was seeking to rebuild Rome and create a metropolis that conformed to his own grandiose vision. Then, in the early hours of July 19, fire broke out in the cook shops and cafes lining the Circus Maximus. The blaze raged for more than a week. The city’s fire brigades were powerless, and the bulk of Rome was left in shambles. According to the historian Tacitus, Nero watched Rome burn while playing the fiddle and singing about the burning of Troy. Centuries later, questions linger. Was the fire an accident, or was it arson? Is Tacitus a reliable witness? Nero blamed the catastrophe on the Christians — is there any truth to his accusation? This episode recreates the conditions surrounding the fire’s ignition and traces the path of the flames using information from excavated remains of Rome’s burnt-out ruins in search of an explanation for one of antiquity’s greatest disasters. (UK/PBS)