Taking you back inside the world-famous Cathedral of Notre Dame de Paris in France. It’s three years since the inferno devastated the vast timber and lead roof and the 850-year-old Gothic masterpiece is now at a critical turning point. Work to rebuild the monument is being ramped up, with 200 scientists, historians, restorers and construction workers now on site. They’re racing to meet an ambitious deadline; to reopen Notre Dame to the public ahead of the 2024 Olympic Games to be held in Paris. 1,200 tons of scaffolding now fills the cathedral, giving the team unprecedented access to every inch of the structure. This not only allows them to restore Notre Dame, but also solve its architectural mysteries.