Location filming in London was carried out mainly in the St Katharine Docks area where older houses were being demolished for housing estates. Partly demolished buildings represented bombed houses and disused buildings were set on fire. St Katharine Docks was one of the few areas of London's East End to survive the Blitz. Many extras were survivors of the Blitz. Aldwych tube station, used as a wartime air-raid shelter, was also used as a filming location. Almost all the period equipment from the London Fire Brigade Museum was used in the film. The night scenes of wartime Berlin were filmed in Donostia-San Sebastian, Basque Country.