Timewatch - Season 25

Eighteen months ago, National Museum of Ireland archaeologists set out to solve a pair of ancient murder mysteries after the discovery of two bodies perfectly preserved by the peat bog in which they had been buried many centuries before. Follow the entire investigation into who these men were, when they lived - and how they died. NEW SEASON 1/6.

A deadly duel at sea - featuring one of the Second World War's great tactical bluffs - is the focus of this dramatised documentary. Commodore Henry Harwood takes on Captain Hans Langsdorff and the pride of the German navy, the Graf Spee. 2/6.

In 1789 the first all-female transport ship set sail from Britain for the struggling colony at Sydney Cove. Three of today's high-flying Australian women trace their ancestry back to the passenger list and find three feisty girls from the Georgian underworld. 3/6.

France 2003: A unit of the American military that aims to bring home all missing US servicemen sifts through the remains of two First World War soldiers. 4/6.

Over 1,300 American pilots were declared missing in action as a result of the Vietnam War. Nearly 40 years on, a special unit of the American military (JPAC) revisits the site where the fighter jet of Major Herman Knapp and his co-pilot Lt David Austin was shot down while returning from a bombing raid over Hanoi. With only 30 days allowed to excavate the site, can JPAC find the servicemen's remains and close the case? 5/6.

Reputed to have been written by Khan's adopted son, 'The Secret History of the Mongols' reveals a very different man to the butcher of legend: a devoted husband, politician, and legislator. This documentary examines the book to show how an illiterate nomad inspired his successors to conquer the largest land empire in history. 6/6.

1179: The Crusaders build a new and supposedly impregnable fortress at a crossing on the Jordan called Jacob's Ford. Within a year of its completion, the castle, which was protected by 1500 Knights Templar, was taken in a siege lasting just five days. Dr Thomas Asbridge is trying to solve the mystery of why the stronghold fell so quickly. 1/6.

When 30 decapitated Romans were found buried in York in February 2005, archaeologists were baffled by their presence. Had these bodies been beheaded because of Roman superstitions about ghosts or were they victims of a brutal act of revenge or war? Timewatch follows the investigation that has since taken place and shows how experts came to the conclusion that these men were caught in a bloody power feud to succeed Emperor Septimius Severus, who died in the city in AD 211. 2/6.

For two months in 1944, the men, women and children of Warsaw faced incredible odds in a bid to liberate the Polish city from Nazi occupation. They did so alone, even though Soviet forces arrived on the scene at the height of the conflict. Told through the personal accounts of those who took part, Timewatch investigates why the Red Army failed to join the uprising as it tells the little-known story behind one of history's greatest betrayals. 3/6.

The first ever exchange of fire between iron-clad ships took place on 9 March 1862 and changed the course of the American Civil War. But what was it like to serve inside these primitive battleships, one of which was dubbed "the iron coffin" by its fearful 19th-century crew? 4/6.

One of America's worst natural disasters struck in the early hours of 18 April 1906. This film marks the centenary of the San Francisco earthquake by revealing the true scale of the catastrophe through the words and images of those who survived. 5/6.

In 1943 the daughter of an Indian mystic was sent into France by the SOE (Churchill's secret service) to provide a vital link with Nazi-occupied Paris. Betrayed and tortured, she revealed nothing of the SOE before being executed. Awarded the George Cross for bravery, this is the story of Noor Inayat Khan. 6/6.