"Nightmare on Downing Street" could be released this October 31. 

When I ask my students in South Korea about which country Halloween comes from, they usually guess America. To which I begin my yearly explanation of the Irish pagan time of Samhain. And if there's one place to be on the island of Ireland for Halloween craic, it's Derry. 

Often described as Europe's biggest celebration of Halloween, the festivities on the banks of the Foyle include a parade, fireworks and plenty of live entertainment with almost every soul in full costume. Revelers come from all over the island and that's the reason why this year may be the scariest ever. 

Read more: This Irish city is the capital of Halloween

Unless you have been living under a rock, you will surely know that Britain's exit from Europe is due to happen that very day. That means that potentially hundreds of visitors from The Republic could get caught up in border check chaos on their way in or out of the city.

The first day of a possible hard Brexit would surely be an administrative nightmare. Traffic tailbacks could be more horrifying than any witches, ghouls or vampires.

Us Northerners often show ironic humor in the face of adversity, so expect to see plenty of Boris Johnson lookalikes and other Brexit-related spoofs.

Just like the old days of Samhain, October 31 will be the day we cross over from the benign powers of The European Union to the dark underworld of an isolated United Kingdom.

Let's hope this Halloween "Nightmare on Downing Street" can be yet averted. That would raise a cheer in Derry!

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