Dyffryn House & Gardens as Country Estate
The Grand Serpent, going by the name Prentis, ingratiates himself with Farquhar, U.N.I.T.'s first director.
“Chapter Five: Survivors of the Flux” Filming Locations
Yaz, Dan, and Professor Jericho hunt across the globe to find out about the end of the world while the Doctor gets her answers.
Doctor Who episode “Chapter Five: Survivors of the Flux” was filmed in Cardiff & Liverpool in the United Kingdom.
Neath Abbey as Space Ruins
Vinder follows Bel's route and discovers Swarm and Azure using more people as energy sources.
Source: Cultbox
National Museum of Wales as Stairs inside the Passenger
Vinder is transported inside the Passenger and meets Diane who he recognizes from his trip through time.
Cardiff Castle as Great Wall of China
Yaz, Dan, and Professor Jericho sneak across the Great Wall of China to leave a message for Karvanista.
St. Donat's Castle (Atlantic College) as U.N.I.T. Dining Hall
Prentis attempts to convince Millington, the current head of U.N.I.T., that he should be considered as a replacement but Millington simply laughs in his face.
House on West Drive (Atlantic College) as Millington's Home
Prentis is waiting for Millington in his car and gives him a snaky surprise.
Source: TheSilverCloak — Twitter via Cultbox
St. George's Hall as St. George's Hall
A local tells Dan, Yaz, and Professor Jericho about the Williamson Tunnels.