Episode #4.1 - S4-E1
Character mistake: Ruth tells the Oxford professor that she read "Classics" at Oxford. That's a major mistake - Oxford doesn't offer "classics" as a course: it is called "Greats" (or "Lit Hum"), and is referred to as such by the students reading it. It might be one thing for an Oxford alumnus to call it "Classics" when speaking to someone not at Oxford, but they would never say it to a member of the Oxford faculty.
Episode #9.3 - S9-E3
Character mistake: Tariq says "I ran a probability logarithm." This makes no sense: it should be "a probability algorithm." (00:17:35)
Episode #4.4 - S4-E4
Character mistake: A computer screen giving details of the villain of the week contains various spelling and grammatical errors: "Embassey", "Assination" and "Assination of with".
Episode #4.1 - S4-E1
Character mistake: Ruth requests a search of London streets with the name "Achilles" in them. A list of streets appears on a computer screen, but when one of them is selected, it is spelled "Achillies."
Answer: They no longer exist. The Military Intelligence groups first appeared at around the time of the First World War. MI-1 was the original directorate, MI-2 dealt with the Soviet Union and Scandinavia, MI-3 with Germany and Eastern Europe, MI-4 handled aerial intelligence gathering, MI-7 dealt with propaganda, MI-8 with communication intercepts, MI-9 with covert operations, MI-10 were the technical experts, MI-11 dealt with security issues out in the field and so on and so forth. All these departments have either been shut down or subsumed into the Security Service, informally referred to by its original designation of MI-5, the Secret Intelligence Service, referred to as MI-6, or GCHQ, the Government Communications Headquarters.
Tailkinker ★