Never mess with British Rail

I was rewatching the Season 12 NCIS episode "So It Goes" featuring a young Dr. Mallard (Adam Campbell, looking not horribly unlike young David McCallum as seen below) and his falling out with his crush and his best friend upon joining the British Army in 1968.

One early scene beings in a train station where Mallard is booking a train from London to Dover (which I've done as well, and highly recommend) and has to deal with a long-winded ticket booth operator (ha! irony!). It's a throwaway scene basically just there to introduce the setup and characters for the 1968 flashback portions of the episode. Normal people might forget it even existed a few days later.

Trainspotters are not normal.

Okay this isn't strictly speaking trainspotting as featured in Trainspotting: from the Railfan Wikipedia page (no, seriously):
Those who are "trainspotters" make an effort to "spot" all of a certain type of rolling stock. This might be a particular class of locomotive, a particular type of carriage or all the rolling stock of a particular company. To this end, they collect and exchange detailed information about the movements of locomotives and other equipment on the railway network, and become very knowledgeable about its operations.
This is more what David Mitchell discusses in his "British Attitude to Food" YouTube rant about how British men get obsessed with things like train numbers.

By "more what" I mean, of course, "precisely what". Because at least one obsessed British man has an entry in the "Goofs" section of the IMdB page for the episode about that scene that is as long as all other goofs combined, even the Doctor Who one (which David Mitchell might also comment on):
When Ducky is waiting at the station in flashback and Maggie walks in, there is an announcement for the next departure over the tannoy as they converse. The announcer states that the next departure from platform 3 calls at "Canterbury East, Ashford, Folkestone Central, Dover Priory, Dover Western Docks". Whilst these are all stations in Kent accessible from London it would not have been (and still is not) possible to take a single train from London to Dover via this route. Although there was once a line between Canterbury and Folkestone it actually ran from Canterbury West via South Canterbury on the Elham Valley Line, but this was pulled up in the mid 1950s and trains did not run direct from London to Dover via this line. Additionally trains from London via Ashford to Dover have always split at Ashford, usually into 'front 4 to Folkestone, rear 4 to Canterbury West' (not Canterbury East) - Ashford actually being the first of the stations listed on the announcement and being the last on the shared portion of the journey. Depending on which London station Ducky is supposed to be in (and sadly even small UK stations look nothing like the one portrayed in this scene, never mind a major station which would have been the starting point of Ducky's journey!) the train may also have called at additional London stations - for example the start of the line via Ashford would have been Charing Cross, the next station being Waterloo East, followed by London Bridge after which the train would call at Sevenoaks, Tonbridge, Paddock Wood and Ashford then Canterbury West OR Folkestone Central and finally to Dover. Alternatively, if the train was going via Canterbury East then the London station would have to be Victoria and the train would be calling at Rochester, Chatham, Gillingham, Sittingborne, Faversham, Canterbury East, Dover Priory. And finally, although in its later years the station at Dover docks was indeed called Dover Western Docks, it was only named this in 1979 and prior to this was called Dover Marine. If Ducky was travelling via Folkestone there is also just as much chance that Ducky would have been travelling to Folkestone Harbour on the boat train as continuing to Dover.
I took the Victoria line, for those of you (almost certainly British) who are interested in it.