The Tower of London is England’s most formidable royal fortress, standing guard on the banks of the great River Thames. It is home to a thousand years of bloody history and is one of Britain's most iconic landmarks. At almost every chapter in London's history, ‘the Tower’ has had a starring role. Built by William the Conquer as part of the Norman Conquest of England in the 11th century, it was designed to dominate London's skyline. The ancient fortifications are set in grounds the same size as those of the White House, but this is far more than just a castle, protecting London from her enemies.

On the surface, London is a buzzing metropolis. But underneath lies secret, hidden worlds, all but forgotten by the millions of people above. These places make up the countless layers of London, and each tells a unique story of the city’s past - successes and failures; victories and tragedies. When the Romans founded settlements along the River Thames during the 1st century AD, they laid down the very first layer of one of the world’s greatest cities. Long buried pieces of the original Roman town still survive to this day – statues, walls, even an entire amphitheatre, where fierce gladiators once fought…and died for glory.

Her Majesty’s Secret Service, or MI6 as it is known, is the world’s most legendary spy agency, thanks to the James Bond stories. Set up in 1909 as the Secret Service Bureau, the existence of MI6 was not formally acknowledged until 1994 — which goes a long way toward understanding the modus operandi of this government agency. This film lifts the veil on the shadowy world of spying.

Secrets of Scotland Yard breaks through the façade of the most famous police headquarters in the world: the very name Scotland Yard is synonymous with all that’s best in the detection of crime. Scotland Yard is the headquarters of one of the oldest police forces in the world – London’s Metropolitan Police Service – known to Londoners as ‘the Met’. Today, 33,000 Scotland Yard police officers safeguard one of the largest cities in Europe, patrolling nearly ten thousand miles of street, more than 200 miles of waterway, six hundred square miles of airspace, 24 hours a day, seven days a week

On London’s world famous Oxford Street, Selfridges department store stands out as a neo-classical landmark. A fact most of its customers don’t realize is this iconic British institution was built by American Mr. Harry Gordon Selfridge - and until he built it, the street was an undesirable back-water. This is just one of many amazing secrets hidden in the story of Selfridge and his department store.