Thatcher Went Through a Lot of Hair Dye
"It became clear that Thatcher dyed her hair constantly and, consequently, it changed color as it faded. The wigmakers used a huge selection of colors in the wig and we revisited it after camera-testing several times to add more highlights."
Thatcher's political achievements were unprecedented, and apparently, so was her specific hair color. "It took a lot of work to achieve the right color and texture hair for Thatcher," Hall said, adding that she prepared for months ahead of production, collecting photo research for each character. Still, it wasn't until she completed a book of images for Anderson's character that she realized the color would specifically be a challenge. "It became clear that [Thatcher] dyed her hair constantly and, consequently, it changed color as it faded," Hall said. "I didn't want to dye her wig to achieve that false golden tone, as I knew it would read badly and be unreliable on camera. So, the wigmakers used a huge selection of colors in the wig and we revisited it after camera testing several times to add more highlights."
According to Hall, because Anderson needed so many color changes, her character required at least three different wigs throughout the season: "We [started] with an iconic golden 'brand Thatcher' wig for episodes one through five, a deeper red tone for episode eight and, finally, a flatter, extra highlighted and thinned wig for episode 10."