The Metropolitan Line (purple) 'leaking' is a reference to actual
drainage replacement works that began in 2016.
The Northern Line, wearing black, is two-faced ("literally two different people") because the Northern line in London is really two lines (the Charing Cross branch and the Bank branch) that run in parallel.
Central Line (red) is portrayed with the stereotypical Essex accent and is also a bit of a slag (another trait of Essex girls) because the counter-intuitively named Central Line goes all the way out to Essex at its furthest extent.
Northern Line pretending to be pregnant and unseating Bakerloo is a reference to the fact that Londoners must give up certain seats on the Tube to a pregnant woman if there is one present and there are no spare seats.
The Bakerloo (brown) and District (green) lines being depicted as geriatric old people is a reference to these lines having the oldest trains on the network (made in 1972 and 1978 respectively) at the time of this video being made, although the District Line has since been upgraded with the newer S-stock trains.
District Line not remembering Metropolitan is a reference to the fact that these are the only two Tube lines (unless you count the Waterloo & City line) that have no direct connections to each other.
Metropolitan working with the Circle Line (yellow) and Hammersmith & City (pink), and the other two getting in her personal space is a reference to the fact that, in central London, these are effectively all one line and share the same track.
Circle line talking in circles is self-explanatory. The Circle line in London is not strictly a complete circle, but comes very close to being one.
The Piccadilly Line (dark blue) is depicted as a tourist because that line in London is the one most often used by tourists. It connects the main airport to some of the busiest tourist hotspots like Piccadilly Circus (London's equivalent of Times Square).
And Leicester Square (pronounced incorrectly) to Covent Garden is a famously short journey that one does not need to take a train for at all. Of course, if you weren't aware of this, it might just seem to you that the train was very fast.
The Jubilee Line (grey) is depicted as the stereotypical sleazy businessman who works in the big office buildings at Canary Wharf. (Bonus fact: this is also the part of London depicted in the Scissor Sisters' video for
Mary, including the establishing shot is of Canary Wharf station, although the train that is shown travelling there is actually on the Victoria line - but that could be explained by the protagonist changing trains at Green Park.)
"Didn't mind
her gap" is a refernce to the gap travellers are told to avoid when stepping between the train and the platform.
The Victoria Line (light blue) talking very, very fast is a reference to
how fast and frequent this line is, even compared to other urban railways. It also gets very hot down there. But seriously though, a train every 90 seconds has got to be some sort of world record.
She also says she "could go all night" because the Victoria line was one of the first Tube lines to operate as a 24-hour service. "could do, but I won't" - because in 2016 when this was filmed, there were some delays in getting this service started.
DLR (in the robot mask) is portrayed as a robot because the trains are self-driving and there is no driver at the front. (Other Tube lines like the Victoria are mostly driverless, but still require a worker at the front to supervise the train.)
The London Overground losing interest in the others is a reference to him no longer being classified as a Tube line, even though he used to be one (the East London line).
Metropolitan lives all the way in Zone 9 because she's the only Tube line that goes out as far as the 9th numbered fare zone.
"Is there a reason you've stopped" because the trains do that sometimes for no reason.
