We follow Thomas Heatherwick’s architects as they battle to keep their glasshouse looking just so, while the engineers struggle to work out how to make them. From chasing bats to giant copper still installation, this episode has engineering and conservation in spades setting the scene for what is one of the most ambitious renovation and building projects in Europe. On site there are constant crisis as the unknown history of this century’s old site comes to light causing unexpected delays. With the weather making it all even harder, the project hits a financial crisis, but will the company hold their nerve and stay true to the original ambition?