Episode #4.2 - S4-E2
Other mistake: There is a scene set in the basement of Thames House. It is one of the most secure buildings in the country, but has graffiti on the walls.
Episode #8.8 - S8-E8
Other mistake: Tariq has been tasked with finding hotel guests who share their surnames with American presidents. His computer screen is shown with the search in progress. The surname "Bush" appears twice (two presidents, but only one surname), and the counts for the two entries are different. In addition, the name "Truman" is misspelled as "Trueman." (00:28:15)
Answer: The shots of the tube station closing and the shot of the concourse were shot at Marylebone station. There is also a shot of the tracks in which a sign is visible pointing to Southwark station and the Jubilee Line, and I suspect this is a stock shot filmed at Waterloo station.
Sierra1 ★