Philip Treacy stands to greet me when I walk into his hotel suite, shaking my hand warmly before sinking into the comfy couch directly opposite. "I like your boots," he tells me with a smile, rising off the couch again for a closer inspection.
We had met briefly the previous night at the V&A Museum in London, current home to the Savage Beauty exhibition - the first and largest retrospective of designer Alexander McQueen's work in Europe.
At a private tour of the exhibition, organised by MAC make-up with whom Treacy has teamed up to create a new signature collection, the Galway man was in great spirits - mingling with guests and engaging in playful back-and-forth with the exhibition's curator Claire Wilcox during her speech.
They had had a fight working together previously, we were told, but neither can remember what it was about. Even when Claire was off mic, I overheard them laughing about the rumble. As Treacy walked around the exhibition, I also overheard him offering those in his select company - which included actress Kim Cattrall - some insight into Alexander McQueen's stunning designs.
So, it comes as a surprise this morning when I arrive to our interview at the famous Claridge's hotel to be told that Treacy will not be answering any questions about his relationship with his late friend and collaborator. Our interview had been already subject to some approvals and a strict stipulation that Philip wouldn't be discussing arguably his most famous clients, the Royal family (he has created headpieces for Kate Middleton, Camilla Parker Bowles and the Queen, not to mention the infamous bow hat he made for Princess Beatrice which quickly went viral online). Discretion with the royals is understandable, but a ban on questions about Alexander McQueen is a rather surprising development.
Nevertheless, there is still plenty to talk about. After all, this is a man who is arguably Ireland's greatest design export and who boasts a client list that reads like an Oscars' seating plan, but who rarely puts himself into the spotlight.
With his collection for make-up heavyweights MAC sitting on the coffee table in front of us, it seems like the most obvious place to start. "I have worked with MAC for 15 years. I was in New York one time and they said, 'will you do some make-up?'" Treacy says of how the collaboration came about. "It's beauty. It's beautification - like hats are too - so it enhances and makes people look better. A lipstick can change your day." Taking inspiration from his own work down through the years, Treacy designed three headpieces (one of which is pictured above) that accentuate the structure of the face, around which the make-up collection was built. The 12 products in this limited edition collection, include rich cream shadows, statement-making eyeliners, and a gorgeous highlighter for the skin, which looks almost too pretty to use. There are also lipsticks in three strong but wearable colours, that are made to last. "I like colour. It's very, kind of, rich," he says.
Treacy's love of colour clearly extends to his own style - today he's wearing cobalt blue skinny jeans that emphasise his slender frame. His hair style hasn't changed over the decades - it's blonde and floppy, falling somewhere between a Byronic hero and a 1990s boyband star. He looks great for a man who turns 48 next month, easily passing for younger.
Born in Ahasgragh, Galway, as the second youngest of eight children, Philip Treacy's father was a baker and his mother a housewife. He made his first hat while studying at Dublin's National College of Art and Design. After completing his degree, he was accepted to the prestigious Royal College of Art in London.
A year later, a meeting with Tatler magazine's style editor Isabella Blow would change his life. He began designing hats for the colourful Blow, who would champion him to anyone who would listen. Soon he was designing hats for all the top designers' catwalk shows, including the then-emerging Lee Alexander McQueen.
From the outset, Treacy's style was whimsical, elaborate, at times radical. Fashion rejoiced at the genius of his ships and butterflies, and during the early 1990s, he was awarded the title of British Accessory Designer of the Year on five occasions.
Today, the self-professed Royalist has an OBE before his name, is unquestionably the world's most famous and most successful hat designer. Treacy's achievements are even more admirable given that they've taken place in an industry ruled by big conglomerates with endless budgets and powerful PR machines. The Philip Treacy brand might be big, but the team behind it is small.
Almost 30 years living in London at this stage, it's understandable that he should have lost his Galway lilt. He speaks with a clear, pronounced, well-spoken, soothing tone, but if you didn't know his origins, it would be hard to place. It's not overly English, but it's not noticeably Irish either.
For the most part, Treacy eschews social niceties and keeps to the point when answering certain questions. To get him to elaborate often requires coaxing. Like when I ask whether he thinks his Irishness has helped him in his career. His reply is succinct: "Of course."
In what way has he found it has helped, I probe. "I don't know how to answer that. It's like asking you what it's like to be Irish. You are Irish. I am Irish. It travels with me everywhere I go."
Does he visit home much? "I don't, really", he says, almost apologetically, prompting me to ask whether that is regrettably so, "Eh yes", he pauses, "I travel a lot, so every couple of weeks I'm going somewhere in the world. My parents aren't alive anymore so there isn't the same reason to go home."
What does he think his parents would make of his career, I wonder? Did they get any sense of how successful he has been? "Not really, my father died when I was 11," he says, grimacing slightly. "I don't want to talk about my parents if that's alright, because sometimes they take it to another level."
I move on to Ireland's upcoming marriage equality referendum, and his thoughts on whether it will be passed. "I hope so, of course," he says, looking slightly flummoxed at the direction the interview has taken. Would he lend his name to it? "I haven't been asked." Would he, if he was to be asked? "It's not really a question I can answer because I haven't been asked."
I wonder did Treacy - who is in a long-term relationship with partner Stefan Bartlett - experience any homophobia growing up in rural Ireland? "I don't really want to talk about that, I want to talk about this," he says, his eyes moving to his make-up collection and then to a MAC representative who's sitting in on our interview.
Then despite his initial reluctance, he musters a response: "Everyone encounters homophobia, it's not just in Ireland. I have had a great experience. I haven't had a victimised experience." Despite the fact that the likes of Lady Gaga publicly gush about his prodigious talent, Philip Treacy manages to keep a relatively low profile. He's not one for red carpet events, or for hanging outside Somerset House during London Fashion Week hoping to be photographed. This is a man, I suspect, who likes to keep his private life private. However, even though I may have asked questions he'd rather not answer, and given that our interview is occasionally peppered with awkward pauses, Treacy is never rude, and at no point does he show any annoyance or frustration.
I steer the conversation back to the safer territory of hats. Well it's relatively safer - as long as you don't call Treacy a milliner. "Millinery actually means a different thing", he clarifies, adding that he prefers to be known as a 'hat maker'. "It's a 17th-century term, what it means is decorating dresses, and I make shapes. I design hats rather than decorate hats."
I tell him that it's remarkable in a youth-obsessed industry that most of the women who've worn his hats best are older - Jasmine Guinness, Isabella Blow, Sarah Jessica Parker who recently turned 50, Grace Jones, Dame Joan Collins to name but a few. Does he think that it takes a level of maturity and an acceptance of oneself to have the confidence to wear a hat well?
"No, not really. All these people are kind of rebels. Hats were worn for conformist reasons at one time, and now they are worn for the opposite reason. All those people that I make things for, they occupy their own space. It's impossible to define someone like Sarah Jessica Parker, she inhabits a kind of," he pauses, searching for the correct words, "people like her, they don't know why they like her. Fortunately because I work with her, I know her, she's a very nice woman, but because of the character that she represents to people all over the world, she can get away with more. She likes fashion, that's her character or persona.
"And then with the other ones, Grace is a tough cookie. I think they're strong women, really. Lady Gaga is very strong. Grace Jones is, Joan Collins. I think what makes them different is they're not worried about what anybody else thinks."
So do you need to be an extrovert to wear a hat? "No, you don't, but it's part of their make-up, really. You don't become those people by conforming on any level, regardless of a hat, so they're fearless. Isabella was fearless," he says referencing his mentor and patron, who took her own life in 2007. "People are afraid of hats, but they shouldn't be afraid, there's nothing harmful about a hat, it's just entertainment on the head."
The reason, I was told at the start of the interview, that he doesn't want to talk about Alexander McQueen - who, like Isabella Blow, took his own life - is that four years on from his death, Treacy still finds it upsetting to discuss. Understandable, they were great friends - a rare thing, I'd imagine, in an industry so renowned for its fickleness.
Having been introduced in 1992 by Isabella, McQueen and Treacy began working together, a collaboration that produced some of fashion's most iconic moments, including Treacy's Butterfly hat. In the years since, there have been countless copies of the hat produced - is Treacy flattered or annoyed by mass imitation?
"It's very easy to say it doesn't matter but I wish people would get their own ideas, that's really the point of developing, you know. I get requests off people all the time, 'how can I develop my business?' Or 'how can I start to sell hats to stores?' You need a style that's particular to you. The stores aren't going to buy it if it looks like my hats because they buy them from me," he says matter-of-factly.
"People are international today. So the person who is shopping in Ireland is also shopping in London, or Paris, in New York. It's not so provincial any more, people are very clued in, so they know when something is completely different and that's what brings about success. People want something that they haven't seen before."
In terms of diversity of customers, no other high-end designer can rival Philip Treacy. His hats are worn by everyone from royalty (36 guests at the 2011 wedding of Prince William and Kate Middleton wore his creations) to wacky popstars to winners of a Best Dressed Lady competition at a rural Irish race meeting. Yet, despite their popularity and ubiquity, they remain a much coveted item across all international social classes. It's accessible luxury.
And while I'm sure there has been the temptation, and indeed the encouragement, to expand his brand to include maybe shoes or handbags, Treacy has remained entirely loyal to his craft. Admirably so.
"Everybody does that. Everyone is doing shoes. Everyone is doing handbags. Everybody is a designer today," he says flashing a smile. "I would love to do all those things but you can't do everything. I could do that if a shoe company approached me and said we'll do the shoes and then you just put your name to it, but I don't work like that."
I'm told our 15 minutes together is up, and swiftly make a plea for one more question, which Treacy agrees to: does he have a career highlight? "I have a career highlight every week, so Dame Joan Collins in Buckingham Palace in a week is a bit of fun. You asked me about my parents earlier, and when I was about 10 going to school, I wasn't allowed to watch Dynasty. I remember, my parents they just thought Joan Collins was a trip. So now when I am talking to her sometimes, I just think, 'God if they only knew who I was talking to'", he says laughing. "Every week is a different project. This week is MAC. Next week is Russia. I am lucky that I have such an interesting job because it makes for an interesting life."
Philip Treacy for MAC is available in Brown Thomas and BT2 stores nationwide and from MAC, Henry Street, Dublin 1