It's been months in the making, and just like any royal event worth a watch, the build up hasn't been without controversy. But tonight we shall see beyond the tears and tax payer spending dramas to Princess Eugenie's very own take on royal pomp and romantic ceremony.
Before you tune in to our live stream (here from 11pm), here are the best details of tonight's event, from the cake, to the guests to the cost of the whole affair.
How it all started
He was working as a waiter in a cocktail bar.
She was sixth in line to the British throne.
But it was no rags-to-riches story for Jack Brooksbank, who is set to marry Princess Eugenie at Windsor Castle tonight in a $5.2 million two-day extravaganza shaping up to be bigger than the May wedding of her cousin Prince Harry and his new wife Meghan Markle.
The event has been tarred with claims of a misuse of taxpayer spending for a non-working royal, and the family have endured the embarrassment of failing to secure public service broadcaster BBC to televise the event.
And then there's the question of how to solve a problem like the mother of the bride, aka Sarah "Fergie" Ferguson, which has long haunted the monarchy.
The couple's love story started in 2010 during a skiing holiday in Verbier, Switzerland where Eugenie's father Prince Andrew owns a ski chalet.
Aged 24, Brooksbank had given university a miss, and was waiting tables and serving drinks at Devonshire Terrace, a bar and restaurant near Liverpool Street in London.
The Queen's granddaughter Eugenie, aged 20, was studying English literature, art history and politics at Newcastle University.
It was "love at first sight", Brooksbank said during a televised interview with the BBC following the couple's engagement in January.
Eugenie is said to have admired his work ethic.
"She is very uncomplicated," a source told the Daily Express.
"She's a doer, a worker, as is Jack. They are very suited.
"Jack's always worked hard. He chose not to go to university so that he could get on the career ladder and Eugenie loved that.
"She didn't care at all that he was a waiter. She might be a princess, but Eugenie comes with few airs and graces."
Brooksbank was formerly known as "barman Jack" among Chelsea party goers.
But despite a working-class job, he wasn't a working-class man.
Brooksbank is said to have already mingled in royal circles before he met his wife-to-be. He was a friend of Prince Harry's before the couple met.
The 32-year-old is a descendant of the Brooksbank baronets and reportedly a distant cousin of Eugenie's. (Her mother, the Duchess of York, is the great-great-granddaughter of Lady Julia Coke, who is the daughter of Jack's great-great-grandfather, Thomas Coke.)
His parents are 68-year-old George Brooksbank, a chartered accountant and company director, and his wife Nicola, 64.
He has younger brother Thomas, 29, a possible candidate for best man.
Brooksbank was educated at Stowe School in Buckingham, where boarding fees are almost $23,600 a term.
Since 2001, his family's address has been an apartment in a gated community in the southwest London borough of Wandsworth, not far from Battersea Park.
After working at pubs and bars, Brooksbank is said to have been poached by businessman and nightclub owner Piers Adam and employed by the Markham Inn.
He went on to manage Adam's Mayfair nightclub Mahiki, a favourite among royalty and celebrities.
In August 2016, he set up Jack Brooksbank Limited, a wine wholesaler, and is also an ambassador for Casamigos Tequila, owned by George Clooney and Cindy Crawford's husband Rande Gerber, who are both expected to be guests at the wedding.
Brooksbank has been described by friends as "kind and selfless" and a perfect match for Eugenie, now 28.
But he hasn't entirely avoided scandal.
In 2013, photos of Brooksbank touching the breasts of a naked stripper while blindfolded and covered in candle wax during his 21st birthday celebrations were leaked online.
The Sun on Sunday reported the story but said the photos were "too raunchy to publish". They were removed shortly after Buckingham Palace was alerted to their existence.
Eugenie (now ninth-in-line to the throne after the births of Eugenie's cousin Prince William's children George, Charlotte and Louis) is the second child of Andrew and Fergie, Duke and Duchess of York.
Their first born, Princess Beatrice, 30, will be maid-of-hour at the wedding.
Eugenie's parents divorced when she was six years old and despite public criticism and stories of royal shunning of her mother, she has described her parents as "the best divorced couple".
Eugenie has faced health issues — at age 12 she underwent back surgery at the Royal National Orthopaedic Hospital in London to correct scoliosis — But she has made a full recovery despite two 12-inch titanium rods in her back.
She boarded at Marlborough College in Wiltshire, where term fees are $25,000, and undertook a gap year before attending university.
In 2013, she moved to New York City to work for the online auction firm Paddle8 as a benefit auctions manager but despite living in different countries, her relationship with Brooksbank flourished.
There are said to have been several Skype calls keeping it alive.
In July 2015, Eugenie moved back to London to work for the Hauser & Wirth art gallery as an associate director and was promoted to director in 2017.
In January, Brooksbank proposed while the couple were on holiday in front of a volcano looking over a lake as the sun was setting in Nicaragua.
"The lake was so beautiful," Eugenie told the BBC.
"The light was just a special light I had never seen. I actually said this is an incredible moment, and then he popped the question, which was really surprising even though we have been together seven years. I was over the moon.
"[It was a] complete surprise. But it was the perfect moment, we couldn't be happier."
They couple live in Ivy Cottage, within the grounds of Kensington Palace, which is also inhabited by Prince William, Kate Middleton, and their three children (Apartment 1A) and Meghan and Harry (Nottingham Cottage).
They pay a "commercial rent" on the cottage, but it's likely a fraction of the true market rate, which would be thousands a week.
Princess Eugenie does not carry out public duties — like the Queen or her cousins — and receives no allowance from the Privy Purse.
She undertakes minimal public engagements but when she does, they are usually connected with the charities she supports, including the Teenage Cancer Trust and Children in Crisis.
There isn't expected to be as much family drama as on the Markle scale (no half brothers or sisters pining for an invite) but Eugenie's mother Fergie is still an awkward thorn in the royal family's side.
She was present as all the finer details of the wedding were discussed at Balmoral over the summer.
It was at the Scottish castle when Fergie came down to breakfast to see photographs of her having her toes sucked by her American "financial adviser" John Bryan, splashed across the front pages in 1992.
She was cast as a royal outsider ever since and has fought to be accepted back into the Windsor fold.
And she isn't one to shy away from the limelight — the Duchess was keen to promote her daughter's big day via the BBC's One Show, where she jokingly referred to herself as MOB, or mother of the bride.
She declared that she and Brooksbank had bonded over Casamigos tequila, saying: "He'll just hand me the tequila and say 'Come on, mother-in-law, down it'."
And the couple are likely to have cringed when the ever-enthusiastic Duchess declared she was looking forward to becoming a grandmother, insisting: "They are thrilled because I write children's books and I'm a child, I haven't grown up."
And after a series of gushing social media posts, in which she referred to Brooksbank as her "son, brother and best friend", she wrote a letter published in celebrity magazine Hello!.
"Dearest Eugenie and Jack The Man, when you walk into a room, you bring smiles to the faces of all who meet you," she wrote.
She's also been criticised over recent "cringey behaviour" including selling juicers on QVC.
But the woman once dubbed the Duchess of Pork by the British tabloids appears to be experiencing something of a royal renaissance.
She was there when at Balmoral, where the Queen was guest of honour at Princess Beatrice's 30th birthday party in August.
The 92-year-old Queen has reportedly made it clear to courtiers that orders from her beloved granddaughter's mother are to be respected.
And although Fergie was left off the guest list for the evening reception of Meghan and Harry's wedding, she is expected to be seated alongside her ex and Princess Beatrice for the ceremony at St George's Chapel, and treated as "part of the family" at the champagne reception the Queen is hosting afterwards at St George's Hall.
She'll also be at the black-tie reception at Royal Lodge, the Windsor home Fergie still shares with Prince Andrew despite their 1996 divorce.
The Queen's cousin, party planner Lady Elizabeth Anson, is thought to be involved in the Friday castle reception. But Bentleys Entertainment is said to be organising the second festival-themed wedding event on the Saturday afternoon — very much under Fergie's direction.
It is the same company Victoria and David Beckham used when they married at Luttrellstown Castle in Ireland.
Fergie's legendary bargaining skills, which have prompted some behind palace gates to dub her the "queen of the freebie", have no doubt been put to good use.
Quite whether the British public share Fergie's enthusiasm remains to be seen.
Although the palace insists it was inundated with more than 100,000 applications for one of the 1200 spectator spots within the castle walls, there was still plenty of hotel accommodation available, reported the Daily Telegraph early this week.
And despite Prince Andrew's best efforts, the BBC refused to televise the ceremony, saying it would be a ratings flop, according to the Mail on Sunday.
ITV has stepped in to broadcast the big day live.
Princess Eugenie is said to have invited 850 guests to St George's Chapel, which out-does Meghan and Harry's 600 invitees.
And like Harry and Meghan, the couple will embark on a carriage ride to wave to well-wishers following the ceremony, an addition that will bump the security bill up to an estimated $3.9 million.
The taxpayer is set to cough up millions for the wedding, which has sparked more than 18,000 people to sign a petition demanding that no public money be spent on the wedding.
Only time will tell whether the second biggest Windsor wedding of the year will live up to the happy couple's expectations.
It is now a two-day affair on Friday and Saturday. The ceremony starts at 11pm New Zealand time.
The ceremony will be at St George's Chapel at Windsor Castle, followed by a reception in the afternoon hosted by the Queen.
The couple will have a carriage procession through Windsor town centre before an evening reception at the Royal Lodge, where Eugenie's father Prince Andrew lives.
On the Saturday afternoon, a festival-themed wedding event will be held at Royal Lodge.
Princess Eugenie has not revealed anything about her wedding dress, other than she will choose a British designer.
Bookies have placed high odds on her picking a couture Stella McCartney gown, who designed Markle's reception dress.
The wedding party
Princess Beatrice of York is maid of honour and Brooksbank's brother Thomas, 29, is in line for best man.
Theodora Rose Williams, daughter of British singer Robbie Williams and his wife, will be a flower girl.
The other flower girls to be are Princess Charlotte of Cambridge; Maud Windsor, goddaughter of the bride and daughter of Lord Frederick Windsor; and Ines de Givenchy, daughter of J.P. Morgan and Co banker Olivier de Givenchy.
Prince George of Cambridge, is a page boy along with Louis de Givenchy, son of Olivier de Givenchy.
Expected among the 850 guests are: George Clooney, wife Amal, Cindy Crawford and husband Randy Gerber, Robbie Williams and his wife Ayda Field, the Beckhams, Sir Elton John, James Blunt, Ellie Goulding, Cara Delevingne, Margot Robbie, Sienna Miller, Suki Waterhouse and Ed Sheeran.
Members of the public have been invited to apply for one of 1200 spectator spots within the castle walls.
The dress code
For the afternoon reception, male guests must wear a morning coat and women are required to wear a day dress and hat (think fascinators and respectful hemlines).
The dress code for the evening reception is black tie.
Estimated at $298,000.
Princess Eugenie has said she wants the wedding to be plastic free.
As Brooksbank is the UK ambassador for George Clooney's Casamigos tequila, they will likely save some money on alcohol but other drink costs are expected to total $166,500.
A rare pink-orange padparadscha sapphire, surrounded by diamonds.
London-based florist Rob van Helden has been chosen for her wedding day blooms, who boasts celeb clients like Pierce Brosnan and Elton John.
Hundreds of thousands of fresh flowers and herbs will decorate the church, Windsor Castle and marquees, Shepherd says.
Eugenie's bouquet must contain a flowering plant called myrtle, according to the decades old custom.
The music and entertainment
Estimated to cost between $40,000 and $108,000 and could include trumpets, bell ringers, organist, choirs, DJs and live bands.
The couple may be able to save money with their famous guests who could thrown in a free song — Goulding, Blunt, Williams, Sheeran and John.
Security is expected to be the most costly element of the wedding bill, making up $3.9 million of the wedding cost and mainly due to the public procession.
Sniper coverage and anti-drone technology is expected.
The estimated cost has been put at $11,000 and Eugenie in August admitted she had been putting together Pinterest boards of possible wedding cakes.