I am familiar with Camden and Mornington Crescent area, but "Shades of Mornington Crescent"?
> The game consists of each panellist in turn announcing a landmark or street, most often a tube station on the London Underground system. The aim is to be the first to announce "Mornington Crescent", a station on the Northern line. Interspersed with the turns is humorous discussion amongst the panellists and host regarding the rules and legality of each move, as well as the strategy the panellists are using.
Although the original host sadly passed away a few years ago, and many of the original cast are well into their 80s...
I'm not sure if this is a valiant attempt to confuse Americans, but this isn't true. Trains stop in both directions.
A reason it might not seem like that is that there are two branches of the Northern line running in parallel between Euston and Camden Town, and Mornington Crescent is only on one of them. So depending on which way you turn when you reach the southbound platform at Camden, you may or may not pass through Mornington Crescent on your way into town.
Nowadays, the next station (Camden Town) and that area's various alternative/subculture markets make the area very busy all the time, so all trains stop at Mornington Crescent at all times.
Train nerds will doubtless be fascinated that geographically it's on the east of the other branch, but on tube maps it's shown on the line to the west.
There are some complicated track crossings in the area and it's easier - and more useful - to keep the branches straight on the tube map than to show what's really happening underground.
The Wikipedia article is fairly anodyne, but the talk page was surprisingly acrimonious on the topic of whether this joke is a game, or whether this game is a joke; ultimately, the side insisting it is so a real game seemed like they were attempting to prevent Wikipedia from "spoiling" it by stating outright that there are no actual rules:
https://en.wikipedia.org/wiki/Talk:Mornington_Crescent_(game...
... which reminds me of the surprising persistence with which some people tried to get Wikipedia to state that drop bears are real:
So GP's last sentence can be interpreted as: "There are similarities to the radio game Mornington Crescent".
I often forget how British phrases, cultural references and idioms can be completely inscrutable.
My girlfriend speaks English as a second language, and speaks it beautifully, but can struggle if I use idioms or phrases which are far more commonplace than this, partly because of how many we have in English and partly because they can be unusual.