Ancient hominid fossils ignite controversy over the origins of humankind.

Disease & Disaster. The Mystery of the Black Death begins in September of 1665, when a tailor in the secluded English village of Eyam opened a flea-infested shipment of fabric from London. In a matter of days, the tailor and much of the village were suffering the telltale signs of bubonic plague, the disease that, in the first five years since its arrival, had wiped out a third of the European population. To prevent the outbreak from spreading throughout the region, the whole town was quarantined — no one was allowed in or out. Outsiders assumed that the bacteria would simply wipe out the entire village. But they were wrong. Three hundred and fifty years later, Dr. Stephen O’Brien, a geneticist from the National Institutes of Health in Washington, D.C., is delving into the reasons why some individuals managed to survive the excruciating Black Death while others were dying all around them. Following O’Brien as he takes DNA samples and investigates historical records and family archives, the film sheds light on the resistance to the plague, and reveals a stunning legacy that the plague survivors passed on to their descendants — a similar resistance to the modern-day scourge of AIDS. (UK/PBS 46 min)

Modern Mysteries. After midnight on April 15th, 1912, an urgent knock woke Swedish Titanic passenger Alma Paulson and her four young children. Alma and her children were told to wait in a sitting room below deck for further instructions, and when they finally made it topside, all 20 of the lifeboats were long gone. As the ship’s tilt increased, it became more and more difficult to hold on. A friend tried to help by scooping up two-year-old Gosta, yet none of the Paulsons survived. Only Alma’s body was identified. Six days later, Canadian rescue workers spotted the lifeless body of a fair-haired toddler floating near the site of the wreck. The sailors were so moved by the discovery that they purchased a small white casket and held a service for the little boy in Halifax, Nova Scotia, which the whole town attended. He was buried in the Fairview Lawn cemetery with other unidentified Titanic victims. In this episode of SECRETS OF THE DEAD, historian Alan Ruffman and a team of scientists headed by Dr. Ryan Parr, co-director of the paleo-DNA laboratory at Ontario’s Lakehead Univeristy, use incredible technology to help provide answers — and closure — for relatives of Titanic victims whose remains were never identified.

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)

(Warfare) In the spring of 1943, nearly 150 highly decorated pilots were ordered to report to a Royal Air Force base in England to begin preparations for a top secret Allied raid. In complete secrecy, the team trained to master the dangerous art of high speed, low altitude night flying. On May 16th, 133 of the airmen boarded 19 modified Lancaster bombers. Each aircraft carried a top-secret weapon — a newly-invented bouncing bomb — designed to shatter Germany’s major dams, stem the flow of water to the Ruhr valley’s steel factories, and, ultimately, undermine the enemy’s ability to produce weapons. In a matter of hours, four of the targeted dams were hit and two destroyed, more than 1,000 Germans killed on the ground, and countless factories and homes left in shambles. The raid took its toll on the airmen — 53 men were lost. Nevertheless, the mission was deemed a success and boosted morale throughout the Allied forces. The mysterious bouncing bombs were the brainchild of Allied aircraft designer Barnes Wallis. How did Wallis come up with this unlikely weapon? How did losing his marbles make it all work? What did he go through to make it functional, and how did the elite airmen ensure its successful deployment?