Ask any fashion person accustomed to the trials and tribulations of transitional weather, and they’ll tell you that there’s nothing better than a trench coat come autumn. Timeless, versatile and, when you choose the right one, an outfit in itself, it’s a capsule-wardrobe staple that never fails to look chic. So imagine my surprise when (to celebrate Barbour’s installation at the Saatchi Gallery, Tartan Reimagined: The Barbour Way) our favourite It girl, Sienna Miller, was spotted wearing something that turns the trench on its head: a dark brown suede trench coat.

In true Sienna fashion, she makes a strong case for the piece. In an almost mahogany shade of brown, the buttery corduroy suede added dimension to her otherwise all-black ensemble, injecting an endlessly chic finish to her black jumper, plaid midi skirt and knee-high boots.