The King’s Speech was filmed here and now Lancaster House, a grand pile by the Mall, became the venue for the Prime Minister’s Speech on Britain’s journey towards a new horizon.

Dripping with gold and full of large, imposing portraits of monarchs, the room chosen for the biggest speech of Mother Theresa’s premiership seemed to be telling the gathering of foreign ambassadors that the grandeur of the country’s imperial past could be regained with a shiny, new EU-free future as Global Britain.

Dressed in a tartan suit, the PM, having for months kept her Brexit plan under wraps, dropping a hint here and a hint there about what Brexit might look like, strode onto the podium with the rather small words “Plan for Britain” as a backdrop.

The question in the minds of everyone amid the neoclassical splendour was: were we going to get a hard Brexit, a soft Brexit, a hokey-cokey Brexit or a flexi-Brexit?

In the end, Mrs M insisted it would be a clean Brexit: out of the single market and out of the customs union; albeit with a new customs deal to minimise all the red tape.

The top Tory spent most of her speech, saying how we wanted to be nice and friendly to our lovely continental cousins; that it was in the best interests of everyone that we did a deal that was fair and open to both sides.

But it was when the PM talked about what would happen if the Eurocrats suddenly turned nasty that her demeanour changed and Mother Theresa became Lady Macbeth.

She warned the euro-crowd before her that if Brussels played hardball and sought to punish Britain for Brexit, then it would be an act of “calamitous self-harm”; that if the UK could not get the deal it wanted, it would walk away; that “no deal was better than a bad deal”.

Indeed, the top Tory insisted Brexit had not only taught Britain a lesson but it should teach the EU one too; that if you do not respond positively to different interests but try to push everything into a “vice-like grip, that ends up crushing into tiny pieces the things you want to protect”.

Was Nicola Sturgeon at this point, shouting at the TV: “Exactly!”

Of course, there was a grand irony to match the grand occasion; Lancaster House was where almost 30 years ago the virtues of Britain being part of the single market and “sweeping away the barriers" to trade were extolled. The speaker? Margaret Thatcher.