The Crown's Makeup Artist: Princess Diana Wore Blue Eyeliner When She Felt "Vulnerable and Targeted"

In season four, we really get to see Princess Diana go from a relatively average teenager to an independent young 20-something. Although this time span proves to showcase an emotional evolution for Diana, her hair doesn't significantly change. "Emma's own hair colour is really similar to Diana's natural hair colour, but Diana's haircut was what defined her look, even un-styled it is unmistakably her." Hall said. "Her wigs throughout the season all have precisely the same 'Diana cut' but vary in colour and styling, becoming progressively blonder and more glamorous [and] voluminous."

Historically speaking, royals have followed bizarre beauty trends (white lead in the Middle Ages was all the rage). However, Mary Greenwell, former makeup artist of Princess Diana IRL once told Stylist that this princess was keen on a consistent skin-care routine to keep her complexion looking as fresh and radiant as we remember. With that said, Hall barely used any base makeup on Corrin's skin while filming some of the earlier episodes in the season. In fact, she used no foundation at all on the actress from episode 1 through 5.

As we go deeper into the season and hit peak '80s maximalism, Diana's beauty look shifts, albeit subtly. Hall said her team used makeup trends specifically from that decade to age Corrin while also emphasising her emotional narrative. "We knew from research, for example, that Diana would apply her iconic blue eyeliner and mascara when she felt vulnerable and targeted," said Hall. This may come as a shock knowing that the royal family dress code can be quite limiting to more dramatic and colourful beauty looks — this is why you almost never see the Queen and Kate Middleton wearing a wine-red nail polish. Alas, this bolder eye look is one that's still largely associated with Princess Diana, even today.