As we scour the red carpets, launch parties and galas of this world to bring you the very best celebrity looks every morning, we also have our eyes peeled for emerging trends and detail that we feel we should draw your attention to.

This week it's the trouser suit. More usually spotted in and around office blocks and water fountains, it's undergoing something of a formal reinvention as celebrities discover it's a no-less glamorous – but, crucially, much more pragmatic and (whisper it) cooler – alternative to a gown for the red carpet or a cocktail party. We've been talking about the fash-ification of the red carpet for a while now, and this seems to be further proof.

Mary Charteris's take, worn to a launch party party in Fortnum, was mannish, double-breasted and pinstriped, while Emma Watson's, at the premiere of her new film Noah, was the classic go-to trouser suit for the fabulous, a Saint Laurent le smoking. Game of Thrones's Sophie Turner also tried the look, as did Shailene Woodley, the star of the much-hyped teen flick Divergent. Then there was Lady Gaga, who test-drove a pink sparkly three-piece with matching bow-tie and wide-brimmed Chupalla hat, because, well, there's no because.

Interesting that it's the younger generation plumping for this – could be that the trouser suit, in the workwear doldrums for so long (because who hasn't had a terrible corporate experience with a shiny rear and sta-prest front pleats?), has now become something of a fashionable rebellion among teen spirits?

Click below to see the rest of this week's red carpet looks