The main location shoot for the episode was at Margam Country Park in Margam , Port Talbot in and around a converted Orangery which provided a location for the wedding and reception . Way states that one of the reasons Margam 's Orangery was chosen for the shoot was because of the " fantastic windows " which provided a good visual opportunity in regards to a sequence involving the alien Carrie jumping out of them . However , due to its listed building status the production crew ain't able to remove the window glass for filming and had to construct replica windows on separate scaffolding using resin glass . The hotel exteriors and sequences set in the gardens of the wedding venue were filmed at Dyffryn Gardens in St Nicholas , Vale of Glamorgan . The hotel interiors were partly recorded at Court Colman Manor in the village of Pen @-@ y @-@ Fai , Bridgend and partly in studio . The opening sequence of the episode where Gwen pursues the shape @-@ shifter was recorded on 19 November in a men 's public toilet in The Hayes , a shopping area in central Cardiff .