![](https://image.tmdb.org/t/p/original/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![](https://image.tmdb.org/t/p/w342/kH4NDOUagtj0J5hau95QGBcy4FQ.jpg)
Helmets, Tea, District Heating
How do they harvest and treat the world's most expensive tea? Plus, how does the Siekierki power plant of Warsaw, Poland heat half the city's homes?
Stars:
![](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![](https://image.tmdb.org/t/p/w300/2NT2eNa2VFZz8kbVa5HFjBHWWV8.jpg)
![](https://image.tmdb.org/t/p/w300/iyx6wAdwj0puKHaZCCbWhuFttLx.jpg)
![](https://image.tmdb.org/t/p/w300/vT3CGfixxJCNqddxec0OPnDyS7t.jpg)
Other episodes for this season
![Aluminium Cans, Cuckoo Clocks, Paddleboards](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Car Shredder, Sarees, Worcestershire Sauce](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Mardi Gras, Rock Candy, Dentures](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Helmets, Tea, District Heating](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Royal Enfield, Art Fraud, Milk](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Crash Testing, Delftware, Umbrellas](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Iron Ore, Wave Flume, Chandeliers](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Oyster Knives, Stadium Lights, Diamonds](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Cheddar Cheese, CPR Mannequins, Dishwashers](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Ford Transits, Driza-bone, Saltfish](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Wood Stoves, Indigo, Synthesiser](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Morgan Cars, Bamboo Cotton, Toilets](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Wind Turbines, Car Tyres, Mushrooms](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Ammo, Dental Drill, Road Markings](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Giant Power Station, Smallest Aircraft](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Crayons, Mirrors](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Electric Race Cars, Mead](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Steam-Powered Boat, Waterwall](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Paving Stones, Tuxedo](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![Fire Gloves, Enamel](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![to be deleted](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)
![to be deleted](https://image.tmdb.org/t/p/w300/4nD5h80cFpzdrlpEzB3JbD1nJ0b.jpg)