The American actress got her start in the acclaimed TV show Freaks and Geeks in 1999, before becoming more famous through her role in 2004 film Mean Girls and as Virginia Johnson in show Masters of Sex.

Though Lizzy has achieved mainstream success and often bares her body in the drama series, she has ruled out getting her kit off for a sake of a few cheap laughs.

“Any time the show requires it and it makes sense, I’m the first one to bravely sign up," she told Nylon magazine.

“I would be shocked if I ever considered doing nudity for a comedy. And I don’t think (Masters) requires me to prove myself in that way any longer. Let’s bring in some new butts and boobs."

Lizzy is also careful not to share too much about her personal life in the public eye, admitting she doesn't want people to know too much about who she is.

“I want them to be able to believe I am who I’m pretending to be at work," she added.

Lizzy previously dated Friends actor Matthew Perry for six years until 2012, and is currently in a relationship with Tom Riley, to whom she got engaged in May (16).

And the brunette beauty is adamant that she won’t be following in the footsteps of other celebrities her age by settling down or establishing a lifestyle brand.

“You won’t see me baking cookies and selling $700 (£572) blankets," the 34-year-old smiled. "Writing a book is interesting, but I don’t foresee that in my future. It just goes back to the idea that I believe I can be better at my job the less you know about me personally."