The Traitors: The stylist behind Claudia Winkleman's tartan chic

The warm hues of the Scottish landscape act as a dramatic backdrop to the majestic castle in the foreground. To the left, the outline of three cloaked bodies huddle around a well but the most striking character stands confidently in the centre, heavy fringed and resplendent in a plum-coloured velvet smoking jacket.

No I'm not looking at a painting in an art gallery. I'm watching The Traitors, where the aesthetic is almost as important as the game.

In particular, host Claudia Winkleman's wardrobe has caught the attention of the style press.

The Telegraph's fashion director Bethan Holt wrote, external: "Forget the drama of Traitors, it's what Claudia Winkleman wears to present the show that has millions of us gripped.

"Are we more excited to see which Fair Isle jumper Claudia styles up next or which contestant will be banished? It's hard to tell."

The person responsible is stylist Sinead McKeefry, who has relished the fashion freedom she's been given in this series.

"For series one, I was only given two weeks' notice to prepare the outfits," she says. "I was on my way to a wedding when I got the call and I had a complete panic. There was a set budget and I had to style 26 outfits for Claudia."

Luckily, the pair had worked together before and get on brilliantly. And they have a similar taste in clothes, so while it was a race against the clock, it was also a good match.

The style and the drama go hand-in-fingerless glove when it comes to creating the success of the show, according to executive producer Mike Cotton.

"Claudia's look adds a certain tone to the programme, which is what we wanted to create. Sinead worked closely with the producers to develop the palette, and it has paid dividends," he says.

McKeefry creates mood boards when planning Winkleman's outfits, and prefers to work alone when coming up with the concepts.

"I had 26 outfits to pull together for this series, two looks per episode. Viewers will notice the challenge look is the same as the breakfast look, but with a coat and wellingtons added in. When it comes to the roundtable, it's an evening look that's more sleek and sultry."

The stylist knows her knits. She studied fashion at Central Saint Martins college in London and went on to specialise in knitwear.

She loves to source unique pieces and, where possible, uses smaller, unknown creators and labels.

"I like to mix up high street fashion with a bit of haute couture, everything we use gets re-used in different looks," she explains.

After every episode airs, McKeefry gets about 600 messages on social media asking where the clothes are from.

"I've been managing the social media myself up until now but I think I'll need some help as I can't keep up with it all!"

Within hours of episode nine airing last week, the red balloon sleeve jumper that Winkleman wore sold out in every size. Knitwear brand Mr Mittens founder Stéphanie Caulier says she "can't believe the positive reaction" since her designs appeared on the show.

"In the fashion world, knitwear is frequently viewed as niche and often overlooked in favour of fast fashion," she adds.

Fashion journalist Stephanie Yeboah says the host - and her stylist - have "absolutely nailed it" during this series.

"She's essentially revamped the British countryside aesthetic in her own unique, punk-led way with oversized bright knits, leather trousers, ruffles, lace and oversized boxy blazers," she says.

Designer Karina Bond agrees that the show's strong fashion sense is "a genius stroke".

"It's like watching a glossy fashion shoot and Claudia makes a great model," she adds.

"The Traitors has such a distinctive aesthetic, from the set to the fashion, everything feels connected. Claudia looks sharp, there's no distractions, and yet the clothes are all statement pieces."

Winkleman wearing a brand's clothes has a bigger effect on sales that a pop star or a Hollywood actress wearing the same piece, she says.

"Maybe it's because the public connects more with a reality show like The Traitors than something that seems less relatable to them, like a film or a red carpet event."

The second UK series, which ends on Friday, has been a huge hit, attracting more than six million viewers. A third series is now in the pipeline.

So what does McKeefry have up her frilly vintage sleeves for the next season?

"You'll just have to wait and see" she smiles wryly. "But I've already started a mood board."

With that, she packs up her bag to meet Winkleman for a series style debrief.