It is a romantic and seductive story: a Prime Minister, out walking in Snowdonia, who is inspired to a moment of epiphany by the majesty of the scenery around her.
That was Theresa May’s explanation of how she reached her momentous decision to hold a snap general election, but the truth is rather more prosaic, though equally fascinating.
Although she took almost the entire Cabinet completely by surprise when she told them about the June 8 poll on Tuesday morning, her closest advisers had known for almost a week, and had been preparing for the news for the past fortnight.
The fact that no-one in Westminster had an inkling of what they were up to is a rare achievement, made possible by the intimacy of her inner circle.
Initially, the only people who knew her thinking were her joint chiefs of staff Nick Timothy and Fiona Hill, as well as her closest confidant of all, her husband Philip.
Mrs May had started talking to them about an early election almost as soon as she triggered Article 50 at the end of last month, and went to Wales already minded to go to the polls.
The potential attempts to jeopardise or frustrate the process in the future became clearer
Insiders say she had been taken aback by the sheer scale of the opposition to her Brexit plans – Jeremy Corbyn made it clear that Labour would vote against the final deal in 2019 if it did not meet a set of arbitrary tests, while the Lib Dems talked of “grinding the Government agenda to a standstill” and the SNP said they had “no intention” of backing the Great Repeal Bill.
As Mrs May told ITV’s Robert Peston on Tuesday: “The potential attempts to jeopardise or frustrate the process in the future became clearer.”
The Prime Minister was surrounded by voices urging her to go to the polls, including William Hague, the former Tory leader, who wrote in this newspaper last month about the “troubles ahead” and the need for the PM to increase her majority ahead of the perilous vote in 2019 to get the Brexit deal through Parliament.
Several senior Cabinet ministers shared that view. They pointed out that Mrs May had a brief window of opportunity for an early election, as Brexit talks will be stuck in the slow lane until France and Germany have held their own general elections between now and September.
Gradually and, as she said in her statement outside Downing Street “reluctantly”, Mrs May began to come around to their way of thinking.
Opinion polls suggested she would win a landslide in a general election, and Mrs May only had to think back as far as Gordon Brown for a prime minister who faced a similar chance to increase their majority, only to hesitate and live to regret it.
Whitehall sources also said the “rhetoric” Mrs May faced in EU council meetings made her increasingly convinced that she would struggle to secure a good deal for Britain as long as EU leaders knew she might struggle to get her own plans through Parliament.
Amber Rudd, the Home Secretary, said on Tuesday: “The point is with the EU they will know we have a small majority. They will watch the polls, see the debates, they read the newspapers.
“It’s important for the EU to realise we have a strong government that is supported by the country so that we can get the best negotiation with them.”
There was, of course, a problem. Ever since she was chosen as Conservative leader – and hence Prime Minister – last July, Mrs May has been steadfast and unswerving on the question of an early election.
“I’m not going to be calling a snap election,” she said shortly after taking office. “I’ve been very clear that I think we need that period of time, that stability – to be able to deal with the issues that the country is facing and have that election in 2020.” She explained that “division in Westminster will risk our ability to make a success of Brexit”, and repeated the message whenever she was asked.
Having already been stung by the experience of the spring Budget, when she was forced to scrap plans for an increase in National Insurance because it broke a manifesto pledge, Mrs May was wary of another about-turn.
During her walks in Snowdonia she discussed the dilemma with her husband Philip, and between them they came to the conclusion that an election was not only in the country’s interests, but overrode any sniping Mrs May might have to endure about a U-turn.
Writing in today’s Daily Telegraph, Mrs May insists: “It is not a decision that I have reached lightly.”
She adds: “The choice [between the parties] is clear-cut, but the decision to call this election was anything but.”
Last Wednesday, when she got back from Wales, the Prime Minister gathered her closest Downing Street advisers around her and told them her mind was made up.
Key party figures were told on a need-to-know basis, but still only a handful of people outside Number 10 were in on the secret. One senior minister who was told of the plan said: “Every time I went to bed and woke up to hear North Korea as the headline on the radio I was delighted.”
Those in the know did not include most of the Cabinet, such as David Davis, the Brexit Secretary, who until late on Monday night was still arranging meetings with EU ministers for an intended trip to Bucharest which was due to happen today.
Instead of visiting Romania, Mr Davis will instead be among MPs voting on whether to override the Fixed Term Parliaments Act and agree to an election in June.
While Mr Davis was finalising his travel arrangements on Monday, Mrs May was on the phone to Buckingham Palace to tell the Queen of her plans for an election.
It was, in effect, a courtesy call, because where previous Prime Ministers would have asked the Queen to dissolve Parliament when they decided to hold an election, Mrs May will be asking Parliament to approve the election instead.
At 9.30am yesterday, Mrs May sat down in her seat at the Cabinet table and, without ceremony, told ministers she had decided to hold a snap election on June 8.
According to one person who was in the room: “It’s fair to say that there was some surprise that it had been so quietly done. There was praise that it had been so quietly done. Everyone had their say. Everyone spoke. It was a sober meeting, there was no banging on the table or anything like that.
“There was total agreement that this was the right thing to do. Sir Patrick McLoughlin [the Tory chairman] made clear that this was one of the most difficult decisions any PM could take but it was the right one.
“There was also discussion of how we mustn’t become complacent because of the opinion polls putting us so far ahead.”
As soon as the Cabinet meeting had finished, Mrs May stepped out of the famous door of Number 10 to share her secret with the world.
As she had promised to do in an interview with US Vogue, the Prime Minister ditched her favourite tartan Vivienne Westwood trouser suit – her “go-to” outfit for major announcements – in favour of a new look, a pinstriped navy blue dress by Daniel Blake. As she had done in Cabinet, she got straight to the point.
“I have just chaired a meeting of the Cabinet, where we agreed that the Government should call a general election, to be held on June 8,” she said.
Labour and the Liberal Democrats were taken by surprise but insisted they would be ready, and Diane Abbott, shadow home secretary, rather optimistically suggested Jeremy Corbyn could be the next prime minister.
At a meeting of the 1922 Committee of Conservative backbench MPs last night, Mrs May made a speech to a room packed with more than 200 people in which she told them to focus on the party’s record in Government when they are campaigning, and not on the weakness of Labour. She did not allow any questions.
As the meeting broke up Conservative MPs banged on the tables and bellowed their approval, chanting “five more years!”
Asked by The Daily Telegraph how the meeting went as she left, Mrs May pointed over her shoulder and said: “Listen to that!”