Taking to Instagram, the 55-year-old shared a bathroom selfie in a purple one piece with a plunging neckline.
The actress' The Royals co-star Genevieve Gaunt commented on the snap, "DREAM WOMAN ALERT."
One follower wrote, "How?! Just how?!" Another wrote, "What a stunner!"
"Wow, how good do you look?" someone else added, while another said, "Like fine wine, damn!"
"Forever 27," one fan said, while many others questioned how she could look so amazing in her 50s.
The comments section was also flooded with fire and heart eye emojis.
Liz has previously spoken about how she maintains her incredible figure, telling The Cut: "I like simple, natural, easy food. I don’t really like food with a lot of chemicals or additives."
"When I’m at home in the country, I always try and eat food that’s grown locally. That goes for meats and vegetables."
"All through summer we eat fruit and vegetables from my own garden. I used to have a small organic farm, and all the meat my son ate was from the farm. Obviously that’s not possible for most people, but supporting local farmers wherever you live is a good thing."
Like Rebel Wilson, Liz has spent a few days at the Viva Mayr health spa in Austria, where they teach their clients the importance of slowing down.
"Viva Mayr taught me to relax," Liz explained to Women's Health. "I learned to sit still, put my phone down, and enjoy my food." And that directly translated into her nutritional well-being: "My digestion has improved since I followed that advice."
While Liz doesn't do "regulated exercise" she is very active and enjoys going for long hikes with her dog, as well as the occasional yoga or Pilates class.
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