Prince Harry and Meghan Markle speak during the Global Citizen festival in New York last year. Photo / AP
Oh to have been a fly on the wall! What would we have seen if we had been inside the Windsor Castle sitting room this week when Harry and Meghan, Duke and Duchess of Sussex, came face-to-face with the Top Lady AKA Her Majesty the Queen AKA his Gan Gan and AKA the head of an institution they have spent much of the last two years publicly denouncing with grim-faced abandon?
Were there finger sandwiches, delicate wee cakes and tea served on fine bone china? Or was lukewarm room temperature tap water poured and left undrunk as this milestone face-to-face finally came to pass?
Here's what we know: On Wednesday, UK-time, the couple flew into London incognito from their home in California with the tantalising question of whether they deigned to fly on a commercial aircraft or borrowed some billionaire chum's private jet so far unanswered.
They spent the night at Frogmore Cottage, that multimillion-dollar source of many, many negative headlines about the couple and for which they repaid the $4 million plus of Sovereign Grant dosh which was used to renovate it.
(These days the five-bedroom joint is home to his cousin Princess Eugenie and her husband Jack Brooksbank, a man whose actual occupation is tequila ambassador. And people say the extended royal family don't have real jobs!)
On Thursday, Harry and Meghan visited the Queen at Windsor Castle, news of which was revealed not by the highest of high royal sources whispering in a journalist's ear but by a busload of visitors who had been at the castle for the Maundy Thursday service and spotted the couple.
One onlooker told The Sun: "I couldn't believe it when I saw who it was. We waved and they waved back.
"They looked happy and relaxed and waved to everyone on the bus. Charles and the Queen were at Windsor Castle at the same time so they must have met them both.
"It was quite the sight. We knew we might see Charles and the Duchess of Cornwall at the ceremony but never believed we would bump in to Harry and Meghan."
(Now that is a story to dine out on at bridge club, if ever I've heard one …)
So secretive was the whole operation, that even the most senior of palace aides were kept in the dark about the Duke and Duchess's lightning visit.
Reports also suggest that the Sussexes met with his father Prince Charles who was at the castle for the Maundy Thursday event along with Camilla, Duchess of Cornwall with the Queen having tapped her 73-year-old apprentice son and daughter-in-law to do the honours for her at the service.
Of the encounter, The Telegraph reported Netflix's most famous hires had "seen" Charles, which does not exactly sound particularly warm or even that it was planned. (It was only earlier in the week that it was revealed Charles would be at Windsor for the Easter event.)
All of which sounds … perfunctory.
While this was the first time that Meghan had set foot on British soil since 2020 this was not some grand rapprochement, a tentative step towards the healing of deep wounds. Rather this all looks like them doing the absolute bare minimum needed to prevent regal noses being put severely out of joint.
Even the Sussexes – two people who last year accused an unnamed member of the royal family of racism and painted the palace as an uncaring institution in front of a global audience of 60 million people – could not have gotten away with travelling to Europe and not seeing Her Majesty without it causing very serious offence.
As their office put it to ITV, the Sussexes "stopped by" to see Charles and the Queen.
This all reads like a bit of a half-hearted, basically-mandatory, kissing of the ring. That this was not about fixing anything but preventing the situation getting worse.
There is one key fact here which underlines that this was not some big fence-mending exercise, all warm hugs and crackling fires and scones being cheerfully passed around.
What is imperative here is not focusing on who they met with but who they did not.
Notably: William and Kate, Duke and Duchess of Cambridge.
If this trip really had been a serious attempt at repairing some of the immense damage done by the events of the last two years then it would have to have included some sort of gesture, however small, in the direction of Kensington Palace.
Just over a year ago, in early April, it was Kate in peacekeeper mode at Prince Philip's funeral who deftly manoeuvred things to get the two royal brothers talking, all done oh-so-conveniently in full view of the UK's press corp. (Handy right?)
What often seems to get lost in the wash these days is that not that long ago, Kate and Harry were friends. Proper giggling-at-the-back-of-the-balcony-scrum-chums. Look at any image of the duo out and about on any sort of engagement and there they are, having what looks like a marvellous time.
William and Harry might have been able to get through several minutes of civilised conversation at Philip's funeral and managed to walk and talk for the cameras at the unveiling of Diana statue last year, without any PR imperative it would seem they have zero interest in seeing one another.
That Harry did not manage to see his brother or his formerly adored sister-in-law is sadly very telling about the state of relations between the two families. No one needs to start worrying about finding a villa big enough for all of them in Greece this summer.
There are other details that only add a certain sting to this warp-speed visit.
Firstly, the fact the whole exercise could be measured in hours.
Next, the fact that Harry and Meghan left their young children back in California carry with it a certain bite. Only a masochist would happily sign up for a long-haul flight with a nearly three-year-old and a baby in tow but the Sussexes's son Archie has not seen his British family since 2019. Likewise, last year the duo co-opted the Queen's pet name for their daughter, calling her Lilibet. The nonagenarian has never met her tiny namesake.
And lastly, a spokesperson for the Sussexes confirmed to ITV that they had visited "The Duke's grandmother." So … he gets his title deployed with all due deference but she is reduced to just being his "grandmother"? That really takes the disrespectful biscuit.
Realistically, this first trip back for the duo was always going to be a sort of toe-in-the-water exercise for all parties but this has ended up being a more dismal, lacklustre showing than even that.
With less than two months until the Platinum Jubilee celebrations kick off, has this regal 'stopping by' broken the ice? Or are we in for a prolonged, painful royal ice age?