Before the flames, the sacred monument Notre-Dame engaged all the senses-with light, height and acoustics; now, researchers strive to restore Notre-Dame's soul: unveiling its true painted stone and ensuring its organ will resound again.

Three years after the devastating fire, Lucy Worsley has exclusive access to the Cathedral of Notre-Dame de Paris at a key turning point of the restoration. Work to rebuild and restore the monument is being ramped up in a bid to meet the ambitious deadline to reopen it to the public in 2024.

Documentary that goes inside what remains of the world-famous Notre-Dame Cathedral in Paris and follows the men and women fighting to secure the fire-ravaged structure.