Keeley Hawes was hurt that people mistook her natural face in "Traitors" as one that had been "aged" with make-up.
The 43-year-old actress stars as senior civil servant Priscilla Garrick in the upcoming Channel 4 thriller and thought it was "cruel" when she read that people thought she had donned wrinkly make-up to take on the dowdy role when actually it was just her normal look.
Keely told The Times newspaper: "I read somewhere that Keeley Hawes had this new look and she has put on ageing make-up.
"I was thinking to myself, "I don't remember that. It is just me with no make-up at all." Which was a little bit cruel to read."
The "Bodyguard" star will appear in the slick new spy thriller alongside Emma Appleton and Luke Treadaway.
Set in 1945 as the Second World War is drawing to a close, "Traitors" tells the story of how a young woman called Feef (Emma Appleton) is recruited to spy on her own government.
Keeley is delighted that her character Priscilla - who works in the Cabinet Office as Feef's boss - is dedicated to promoting women's rights in the workplace in post-war Britain.
She said: "Being a woman in such a male environment was hard and she is just brilliant at it. She says to Feef, "Do you think I don't know how to do my hair? Being attractive is just not part of something we can do."
"And it is so alien to us now, but women still against things like it in the age of Me Too, the way Feef is treated and Priscilla has to look and behave to have a career.
"People are more than their work and I loved that Priscilla was a member of the Gilbert and Sullivan society, but Priscilla and her colleagues are serious people and they are building everything back up."
The six-part drama begins on Sunday 17th February at 9pm.