Her chestnut locks have barely changed in volume and length since her turn as a Bond girl in 1973's Live and Let Die.
Now, Jane Seymour, 70, has revealed her exact haircare routine for maintaining that age-defying, thick, glossy mane.
Speaking to the Mail on Sunday's You magazine, the award-winning actress said: "I wash my hair and condition it every day."
Products in her bathroom include Phyto shampoo and volumiser, as well as a daily hair mask and a Ouai leave-in conditioner.
While Seymour is not fully grey, her hairdresser Marie Ferro colours her hair every three to four weeks with Goldwell products, and uses a "natural weave of three colours".
The Wedding Crashers star – who has four children – also tries to stay away from heated styling tools "as much I can".
Additionally, she "cannot live without" a Mason Pearson nylon and bristle hairbrush.
Finally, given her location in California, she always uses a hat to protect herself from the strong sun rays.
Seymour added: "I personally feel that beauty is the essence of your authentic self."
Speaking in November to Yahoo Entertainment, she attributed her youthful looks to more than just good genes.
The actress said: "It’s about healthy living. It’s about taking good vitamins. It’s about drinking lots of water. It’s about having a positive attitude.
"Everything in moderation. I suppose that’s my mantra.”
Before that, Seymour previously told Hello! magazine that her "intention is to age as gracefully as I can".
She added: "Inside, I’m 20 years old. I was way too serious when I was that age. I’ve found my 20-year-old alter ego, it just happens to be in this body. But that’s okay. I’m having fun and I love it.”
The Hollywood star added: “I try to stay away from sugar and fried food. I very rarely eat meat.
“I eat what I grow in my garden. Fresh fruits and vegetables are my favourite thing in the world.”
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