Tomorrow the US will get a new president, the Western world will get a new de facto leader and - if the more hysterical comment pieces are to be believed - the seal will be loosed on a wrath of demons which will flood forth from hell and lay waste to all the world until the end of time. Plus, there may be an accompanying tag-team of the Four Horseman of the Apocalypse.
In all likelihood, it won't be quite that dramatic. However, what is assured is that Donald Trump's inauguration will be the hot topic at office watercoolers, bus stops and factory floors. So don't be left out of the conversational loop: pretend you know what it's all about with our cut-out-and-keep Bluffer's Guide to the Inauguration:
WHAT: The United States Presidential Inauguration
ALSO KNOWN AS: Swearing-In, Donald's Big Day Out, Barack Obama's Leaving Do.
WHEN: Noon on Friday (that's 5pm our time - just late enough for you to start drinking to celebrate or induce amnesia). It always takes place on January 20, unless that's a Sunday, in which case the new boss takes over on the Sunday but they don't have the public ceremony until the Monday. Got that? Me neither.
BUT BEFORE ALL THAT: Wreath-laying at Arlington, Virginia, and a "welcome celebration" for Trump and Mike Pence today.
AND: The new president may or may not spend the night before at Blair House, as is customary since the Jimmy Carter era.
ALSO CUSTOMARY SINCE THE JIMMY CARTER ERA: Making jokes about Jimmy Carter's comical teeth.
WHERE: Washington DC on the steps of the United States Capitol Building, where DT will give his first address after taking the Oath of Office.
WHICH GOES: "I, Donald Trump, do solemnly swear that I will support and defend Donald Trump against all enemies, foreign and domestic, and bear true faith and allegiance to Donald Trump. So help me Donald Trump." Or words to that effect.
GREAT QUOTES FROM PREVIOUS ADDRESSES: "The only thing we have to fear is fear itself" - FDR; "Ask not what your country can do for you, ask what you can do for your country" - JFK; "Yes, these really are my own teeth" - Jimmy Carter (okay, maybe not that last one).
PREDICTED LENGTH OF SPEECH: 20 minutes.
OFF-TOPIC RAMBLING QUOTIENT: Expected to reach 60pc.
INAUGURATION SLOGAN: "Make America Great Again!" - the Donald's campaign catchphrase, with added exclamation mark. What, you expected something along the lines of "I love you, you love me, we're a happy family"?
HOW MANY PREVIOUS: There have been 44 presidents, 58 inaugurations, 0 candidates whose rise to the ultimate post was satirically predicted on The Simpsons.
INAUGURATION PERFORMERS (PAST): Mickey Rooney, Frank Sinatra, Barbra Streisand, Fleetwood Mac, Bob Dylan, Ricky Martin, Jessica Simpson, Aretha Franklin, Kelly Clarkson, Beyoncé, U2.
PERFORMERS (PRESENT): The Radio City Rockettes, Jackie Evancho, The Mormon Tabernacle Choir. Yes, they're all rather unfamiliar to us, too, although the Rockettes previously did their high-kicking duty for George Dubya (both times).
PERFORMERS WHO WON'T BE THERE: Kiss, Elton John, Andrea Bocelli, Celine Dion, Kanye West and Idina Menzel (Elsa off Frozen to you and me), among others.
DONALD'S REACTION ON TWITTER: Shouty, lots of capital letters.
NUMBER OF TICKETS FOR CEREMONY: 250,000.
SECURITY DETAIL: Secret Service, Homeland Security, Federal Protective Service, Armed Forces, Capitol Police, Park Police, Metropolitan Police of DC, Superman, Batman, Captain America, James Bond, Inspector Gadget, Dangermouse, the dad off The Incredibles, probably Bono et al.
THOSE AGAINST: There's a whole mass of protests planned for the days before, during and after, in Washington and elsewhere, of a bewildering variety. They include: #Trump420 (smoke dope to show your disapproval), Four Women for All Women (a 252-mile run from Harlem), and the Daddy, or rather Mammy, of them all: the Women's March on Washington (that's the one with the crochet hats shaped like vaginas). Or Central Bank Plaza in Dublin, at 5pm tomorrow.
IRISH CONNECTIONS: Mike Pence has Clare and Sligo roots. Meanwhile a brilliant Farmers' Journal headline reminded us that a "Clare landowner" had landed the "big job in US".
FIRST INAUGURATION: George Washington in April 1789.
HIGHEST INAUGURATION: LBJ, on-board Air Force One after the Kennedy assassination in 1963.
MOST UNCOMFORTABLE INAUGURATION: Gerald Ford, succeeding his disgraced predecessor Richard Nixon in '74. Awkward.
COLDEST INAUGURATION: Ronald Reagan (he of the Tipperary forebears) had his ceremony moved indoors because of wintry weather in 1985.
INTERESTING FACTOID: In 1925, Calvin Coolidge's second spin on the merry-go-round was the first inauguration broadcast on radio. In 2017, Donald Trump's may be the first inauguration live-tweeted by the president himself. #WINNING
BIZARRO FACTOID: In 1953 Dwight Eisenhower was lassoed by a cowboy on a horse as he reviewed the parade. How in the name of Gene Autry did this idea get the green light from the organising committee?
HOW TO WATCH: Working chronologically backwards but patriotically forwards, live coverage begins on RTÉ One at 4.15pm, BBC One at 4pm and Sky News at 3pm. Alternatively, try Twitter.
DO SAY: "Five minutes into his presidency already, and it's been a pretty solid start so far. As in, nobody has nuked Tehran yet."
DON'T SAY: "I really miss the last guy."
Come 20 January, President-elect Donald Trump will be officially sworn into office, taking the title ‘President of the United States’. Hell is expected to consume America soon after.