Another day, another A-list hair transformation. This time it's Lily James confirming that the perennial trend for going blonder in summer is indeed alive and well (despite Nicola Peltz-Beckham, Jessica Alba and Phoebe Dynevor all veering to the dark side, sartorially speaking).

James paid a visit to her trusty hair colourist John MacPherson, based in West London, for the colour change where he took her from "brunette to blonde", as he shared on Instagram:

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In place of James' previous warm, chocolatey brown is a multi-tonal soft buttery blonde that has a much more natural feel compared to the blonde wig the actress sported for her role as Pamela Anderson in Pam & Tommy.

pam  tommy    set in the wild west early days of the internet, pam  tommy tells the incredible true story of the pam anderson lily james and tommy lee sebastian stan sex tape stolen from the couple’s home by a disgruntled carpenter seth rogen, the video went from underground bootleg vhs curiosity to full blown global sensation when it hit the web in 1997 a love story, crime caper and cautionary tale rolled into one, the eight part hulu limited series explores the intersection of privacy, technology and celebrity, tracing the origins of our current reality tv era to a tape seen by millions but meant to have an audience of just two pam lily james, shown photo by erin simkinhulu
Erin Simkin

We're also stuck by the shine that James' hair has maintained, not just because chemically colouring hair can compromise its condition. Dark hair reflects light whereas blonde hair absorbs it, meaning it's hard to get a healthy, reflective sheen like this whether your blonde is natural or not. However, it appears that MacPherson used a double-pronged approach to maintaining James' hair health during the colour process, given his use of the hashtags #redkenshadeseq and #k18hair.

Redken's Shades EQ is a next-generation hair glossing treatment that is applied professionally in salons. The formula grants healthier looking and feeling hair complete with megawatt shine. The K18 Leave-In Molecular Repair Hair Mask is a home-use treatment that's shot to cult status for its signature K18Peptide™ that restores hair's elasticity and bounce, making it a perfect treatment for bottle blondes.

Leave-in Molecular Repair Hair Mask K18

K18

Leave-in Molecular Repair Hair Mask K18

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If you're tempted to transform your hair, first heed the advice of Nicola Clarke, the A-list’s authority on blonde hair, with these 5 things to consider before going blonde.

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