 Filming for the episode 's outdoor scenes began in the afternoon of 11 March . The first outdoor scene filmed was the cold open , on West Mound Crescent in Tonteg . Two scenes were filmed in Pontypridd on 12 March : exterior scenes of the Noble household took place on Hawthorn Road — rather than the usual location in Cyncoed — before relocating to Market Street in the town centre to film the scenes where Rose encounters members of the public in the middle of a riot . Tennant and Tate meanwhile filmed the trailer for the fourth series because they were not required on location . 
