We're used to seeing the Duchess of Cambridge with her face turned towards the cameras, but Kate kept fans guessing with a teasing video on Friday, as she looked forward to the launch of her new Hold Still photography book.
In a clip that showed the royal placing a book by a fountain at Kensington Palace, we got a glimpse at her bold red coat - just as easily mistaken for a flowing wrap dress with a leg split - which moved beautifully in the wind.
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In pictures from her later engagement, it was revealed that Kate's elegant button-up is from Eponine London - one of her favourite British labels.
WATCH: Kate teases fans on the day of her book launch
The beautiful coat dates back to the brand's Autumn/Winter 2018 collection, so it may well have been in the Duchess' wardrobe for some time!
She also carried a new DeMellier top handle handbag with gold bar details, and added her Mappin & Webb diamond earrings. Her Ralph Lauren 'Celia' pumps finished the look.
Kate wore a coat from Eponine London
Friday morning's post was captioned: "Let the search begin! We've joined @bookfairies_uk for the day to share copies of Hold Still around the UK with you.
Kate managed to look elegant even with her back to the camera!
"Each copy is adorned with a gold book fairy sticker, gold ribbon, and has a letter from The Duchess tucked inside. To make this activity even more special, book fairies, the Hold Still judges and participants of the final 100 images are leaving copies at places that gave them hope during the lockdown."
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Montreal bag, £425, DeMellier
It concluded: "This special book documenting the unique collection of photographs goes on sale today in UK bookshops and online."
KATE WEARS: 'Empress' earrings, £1,500, Mappin & Webb
The Hold Still book has been put together with support from The Co-op, which helped run the community exhibitions on billboards and outdoor poster sites in 80 towns, cities and areas last October. The final 100 images were first displayed in a digital exhibition on the National Portrait Gallery's website.
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Ralph Lauren 'Celia' pumps, £520, Farfetch
Net proceeds raised from the sale of the book will be split between leading mental health charity Mind, and the National Portrait Gallery. The funds will help to support arts and mental health projects across the UK, including Mind's work in local communities and the National Portrait Gallery's education and community projects.
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