In this episode the drones fly through a forest with a deadly secret, across Britain's newest piece of land and into the hidden stately pile of an unconventional aristocrat.

Presented by Sir Tony Robinson, in this episode the drones fly through a village erased from the maps, a supermarket without any customers, and a platform in the ocean that claims to be an independent nation. The flight starts in Scotland, where just a few miles from the Forth Bridge the largest aircraft carriers ever built for the Royal Navy are under construction. Security in the dockyard is tight, but with each carrier weighing 65,000 tonnes and the flight deck measuring 4.2 acres, it's hard to keep them under wraps! Then the drones head to Nottinghamshire, to an unmarked building. Inside it looks like a supermarket, but there are no tills, no queues and the public are not allowed in. It's not on any official list of stores and the only shoppers to be found are professionals working through the night to prepare online shopping orders. From here the drones fly to the Kent coast where a World War II shipwreck looms over the town of Sheerness - packed full of high explosives.