First came a teasing invitation to the launch party for James Dyson's latest "mystery" invention, which carried an image of a whizzing yellow spheroid on the front. Next, there was a phone-call from one of the inventor's in-house PR team, whose words I initially thought I had misheard.
"I can't tell you anything about it other than its name at the moment," she said, "but James Dyson is happy to come to your office next week to show you how the new product works."
As promised, Dyson turned up in the lobby of The Independent with his marketing manager and his latest vacuum cleaner in hand, for a personal demonstration and a chat.
I was flattered enough for a moment to think he had carefully selected The Independent for an exclusive interview, but it turned out that it was not just our lobby he was vacuuming that day with his new creation. He was carrying out a marathon tour of London's newsrooms, with me sandwiched between the Financial Times and The Sun, culminating in an extravagant 5pm launch at the Oxo Tower in which giant, yellow balls were released into the Thames while 100 journalists sampled the product on test rigs.
Dyson began his PR extravaganza at 7.30am on 14 March by giving a demonstration for the Evening Standard in South Kensington, before moving on to the Financial Times at Southwark Bridge. From there, he headed to The Independent's lobby, where he plugged in his product and glided it around the carpet for 20 minutes to show its "manoeuvrability". Thence he was spirited away to Wapping to do the same routine at News International with The Sun and The Times. Then it was on to Farringdon and The Guardian, before speeding off to his official launch, which had press attending from Germany, Austria, Turkey and Spain. And the newspapers he didn't get round to seeing were visited by his marketing team in the following days with the new vacuum in tow.
I have heard of salesmen coming door-to-door with dusters but this was the deluxe version, conducted in person by one of Britain's most prominent businessman, who is reputed to be worth £800m. At least it could not be said he was doing it for the money.
The next morning's cuttings reflected the reporters' delight at being given an the opportunity to interact with the charming entrepreneur. Reports in the Daily Mail ("Dyson rolls out the vacuum on a ball"), the Evening Standard ("Clean Sweep"), The Scotsman ("From Ballbarrow boy to a millionaire visionary"), The Times ("How new Dyson will clean out the wallet"), the Daily Express ("Dyson rolls out £350 'wonder' vac"), The Mirror ("Dyson Has a Ball"), the Daily Record ("Having a Ball Doing the Cleaning"), The Independent ("Dyson rolls out his latest idea, the vacuum cleaner on a ball"), The Guardian ("Eat my dust: Dyson starts his Ball rolling") all carried detailed descriptions of the new gadget and Dyson's carpet-testing antics.
Let's be realistic, had it been any other vacuuming company, how much attention would newsdesks have paid to its latest invention?
So who was behind this PR coup that ditched the usual press releases and lame stunts in favour of a grand tour by the man himself?
It turns out not to have been the brainchild of publicity wizards hired at great expense, but rather the work of Dyson's four-strong in-house marketing team, who usually deal with the company's educational and charitable activities.
Clare Mullin, Dyson's marketing director, who has led the team since 1995, is modest enough to say that last week's blanket coverage was not the result of a finely executed PR masterplan, but that it personified Dyson's personal style.
"The reason he goes out to see journalists when a new product is launched is so he can judge people's reactions to it. He is genuinely interested in seeing what other people think about the product after he has spent so long creating it. He respects what journalists have to say. It's a good way for him to gauge what people think," she says.
Mullin says that the technique originated in Dyson's early days as an entrepreneur when he could not afford a PR budget. He has stuck to the same routine ever since.
"At the beginning, he did not have any money to do anything. He was on his own with three engineers and an enormous bank loan. He thought: 'I'd better go and see what people think of this'," she says.
While Dyson has more than enough turnover for a substantial PR budget now, more than a decade after his groundbreaking "no-loss-of-suction" bagless vacuum was launched, he obviously realises the benefits of the personal touch and sees the power of maintaining direct engagement with the journalists writing about him.
Kate Nicholas, the editor-in-chief of PR Week, says that the method was employed to conflate the identity of the product being sold cleverly with the personality of the charismatic chief executive who is selling it. "He is encouraging the complete identification of the personality with the brand, in the same way that Michael O'Leary, the CEO of Ryanair, and Stelios Haji-Ioannou, of easyJet, are encouraging the media to see them and their values alongside the product.
"By doing [this PR exercise], he is saying: 'This is a product I care about so much, I'm willing to come and show you how it works. I have invested in it intellectually, financially, and emotionally. I'm willing to come out to you and talk to you about it.'
"It seems as if he is moulding himself along the same lines as Richard Branson, who engages on a grass-roots level," she concludes.
And how much more grass-roots can a chief executive get than by vacuuming the boardrooms and lobbies of the national press?