The worst floods in years hit the exterior filming location in the Berkeley Estate on the first day of the location shooting.
Both of the main filming locations had little or no access to power.
Part of the cave location was used for shelter during air raids on Bristol during the Second World War and prams, shoes and other articles of clothing from this time are still there.
The underground filming location, Bristol's Redcliffe Caves still had 17th writings carved into the walls to protect from Witchcraft.
Redcliffe Caves was originally mined to create the world famous Bristol glass.