Helena Bonham Carter is Princess Margaret in The Crown.
COMMENT
Thatcher likened Balmoral visits to 'purgatory', Diana hated it and Boris broke the rules, says Rebecca Reid. So who passed the Balmoral Test?
The best (and most uncomfortable) episode of series four of The Crown is titled The Balmoral Test.
It sees PM Margaret Thatcher and husband Denis decamp to Scotland for the compulsory royal "holiday" that all heads of UK government are obliged to undertake.
Because, when you're working a 100-hour week running the country, what could be more relaxing than a week at your boss's house?
Would you pass The Balmoral Test? Scroll down to find out
The episode's name is in honour of the complicated and unspoken code of conduct for visitors to the Scottish castle.
In this episode, the rampantly suburban Thatcher fails miserably, coming down dressed in black tie at 6 o'clock in the evening.
Diana Spencer, who arrives just as Maggie is heaving a sigh of relief and heading home, passes with flying colours.
Guests are apparently expected to join in outdoor activities (mostly field sports) with enthusiasm, change outfits up to five times per day, and throw themselves in to eating, drinking and party games - all while remembering royal protocol and making sure not to tread on the dogs.
The BMT goes back further than you might imagine, in fact Prince Philip and Elizabeth Bowes-Lyons were both apparently subject to it.
According to Michael Paterson, author of A Brief History of the Private Life Of Elizabeth II, Philip passed the test on the basis that he had been at school in Scotland and loved all things outdoors.
While the Queen's mother pleased everyone, Wallis Simpson failed quickly by remarking that the tartan carpets would "have to go".
Doing well at the BMT doesn't mean you're going to be a perfect fit for The Firm, though.
The Crown makes much of the fact that Diana went down such a storm on her first visit that pressure was put on Charles to pop the question.
Unfortunately her enjoyment of the place didn't last.
She was subsequently "unhappy and bored" at Balmoral, telling Andrew Morton: "Instead of having a holiday, it's the most stressful time of the year. It's very close quarters."
Kate Middleton made her first visit in 2009, two years before she married Prince William.
According to Katie Nicholl, author of Kate: The Future Queen, the Queen apparently told her grandson's girlfriend that she was welcome to take photographs on the estate - something that is usually forbidden, and suggests the trip was a success.
The Duchess isn't the only Middleton to have undergone the test.
In 2010, her parents were invited to a shooting weekend at Balmoral which was widely (and correctly) regarded as a sign that an engagement was forthcoming.
The Middletons must have passed muster at least well enough to have been invited back: in 2016, Carole Middleton was seen being driven from a shooting lunch by the Queen herself.
Being chauffeured by HRM is considered one of the biggest stamps of approval you can get while visiting Balmoral.
There was endless speculation ahead of the Sussexes' first Scottish trip.
It's rumoured that Meghan Markle visited the Queen in 2017, in the early days of her relationship with Harry.
But the first official stay came a couple of months after they were married.
While little is known about her test performance, the Duchess is famously opposed to hunting and shooting, which are Balmoral's main pastimes.
Perhaps the most impressive faux pas belonged to Sarah, Duchess of York.
Fergie was staying at Balmoral when The Sun ran photos of her having her toes sucked by businessman John Bryan.
Presumably, it made for an awkward family breakfast.
It's not just potential love interests who are subject to the BMT, though.
Margaret Thatcher got off on the wrong foot by arriving without any outdoor shoes (something The Crown uses as a weighty metaphor throughout the Balmoral episode).
She then allegedly spent much of the trip working, which the family found distasteful and inappropriate.
The feeling that the trip hadn't been a success was clearly mutual because, according to the Queen's biographer Ben Pimlott, Thatcher likened her visits to "purgatory" and an official noticed that she "couldn't get away fast enough".
Cherie Blair reportedly wore trousers to lunch, refused to curtsy and took a dim view of field sports.
According to Paul Scott, author of Tony & Cherie, she made the cardinal mistake of not drinking much, and compounded that by commenting on how much everyone else was drinking.
To top all this off, Alastair Campbell claimed in his diaries that she asked the Queen whether it was true that Queen Victoria had an affair with the Balmoral ghillie John Brown, although Blair herself denies any awkwardness between her and the Queen.
Blair later told the world that the conception of her son Leo happened because she was too embarrassed to pack what she referred to as her "contraceptive equipment" when staying at Balmoral, as she knew that staff would unpack her bags for her.
While it's unlikely there's an official rule about bonking at Balmoral, it's not a stretch of the imagination to think that her Majesty might not have been best pleased that details of a Balmoral conception were shared.
The most controversial Balmoral attendee of recent years might be Boris Johnson, who went with fiancée Carrie Symonds.
Their visit was political as the Prime Minister was the first person to attend publicly with a partner to whom he was not married.
Previous to their visit, unmarried couples were expected to spend time at the house during the day, but to sleep off site.
Johnson and Symonds did, however, stay overnight.
The Queen, as the head of the Church of England, was reportedly uncomfortable with the arrangement.
Given that the Queen describes prime ministers as "nobly enduring" the games at Balmoral, and that she by all accounts values her private, uninterrupted holidays in Scotland, one might question why the tradition continues.
It sounds like the only people really benefiting from this combination of politicians, romantic prospects and royals are the makers of The Crown.
Upon arrival at the castle, staff are unpacking your case. What are they going to find?
a) You've snuck in a load of paperwork that you're planning to read by the fire and you haven't brought any outdoor shoes.
b) Evening wear by sensitively chosen Scottish designers, photographs of your dogs, Hunter wellington boots.
c) Ancient Barbour, Le Chameau wellies, taffeta evening dress that smells a bit moth ball-y but stunned at the 1986 Hunt Ball.
d) A trouser suit and a copy of A Vindication of the Rights of Woman.
It's time for drinks. What are you having?
a) A nice sherry, please.
b) Californian pinot noir.
c) Gin and dubonnet
d) I won't, actually. Gosh, what a lot the rest of you are getting through.
What time are you getting up the next morning?
a) 5am - to sneak in some work before anyone else wakes.
b) I'll be leading a sun salutation outside. Or at least trying to. This is Scotland.
c) I'll have made discreet enquiries about what time breakfast is served and be down at nine.
d) With enough time for a Balmoral quickie before breakfast.
How are you spending your last day at Balmoral?
a) Setting off home early claiming a work emergency.
b) Spending time in nature (and Instagramming it).
c) Stalking and then a barbecue.
d) Explaining why I don't approve of field sports.
It's been a week since you left Balmoral. How have you said thank you?
a) A card, with 'Thank you' on the front.
b) A gushing Instagram post, tagging your host.
c) A letter, making sure never to open with the words 'thank you'.
d) A much struggled-over note.
How did you do?
Mostly As
You might be considered middle class by the rest of the world, but here your suburbia is showing. You're relieved to leave, and they're relieved to see you go.
Mostly Bs
You're a breath of fresh air, bringing a new perspective to old traditions. At least you are until the field sports are replaced with nature hikes and conversations about privilege.
Mostly Cs
Of course you've passed the BMT with flying colours. You mop the floor with everyone during charades and find a Corgi willing to sit on your lap.
Mostly Ds
You've had a lovely time nobly enduring each other, despite the culture clash.
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