Episode #1.1 - S1-E1
Factual error: The series is set in 1933, as the initial captions show. Yet the locomotive pulling the Orient Express is a JNR Class C58: the C58 series was built starting from 1938 (C58 239 used here is from 1940).
Episode #1.2 - S1-E2
Continuity mistake: When the equivalent of Miss Debenham tells the Colonel that reaching the 12 people figure might be difficult, her hands and the secretarys are in a different position compared to the previous shot (hers are raised, his are crossed in a different pattern). (00:45:45)
