Naomi Watts on how she conquered fear of working with Bill Murray

Naomi Watts is known for her Oscar-nominated roles in "The Impossible" and "21 Grams" and blockbusters like "King Kong" and "The Ring."

Now, she stars alongside Bill Murray, playing his pregnant, Russian stripper girlfriend in the new comedy, "St. Vincent."

The story follows Maggie, played by Melissa McCarthy, whose long work hours force her to leave her son with their gambling-addicted, alcoholic neighbor Vincent, played by Murray.

"It was an incredible break for me not having done that much comedy and to be in the middle of those two people, two of the great comedic geniuses," Watts said on "CBS This Morning."

But even for an actress of her caliber, Watts said acting with a comedy genius like Bill Murray was intimidating.

"The anticipation of it was terrifying," she said. "I just thought this is going to be so scary because he's so good what he does. I heard he doesn't suffer fools and doesn't fall in love with everyone right away, and so I was kind of terrified and just not having done comedy before or for a long time."

To face her fears, she made use of her newly found, ear-catching Russian accent.

"I decided the only way to approach it was to arrive in character and not give him a chance to see any of my fear and so I had the accent down and I also knew that I'd be improvising with him because, you know, he goes wherever he wants to go," Watts said.

Watts assured the accent didn't come without work. An actress born in England and raised in Australia, she turned to one unique source to harness her persona.

"I found this little Russian spa in the West Village and went there and got manicures and taped these women," she said.

Her goal was to terrify Murray with her new tongue.

But that wasn't her only challenge. She also had to learn how to perform with a prosthetic baby bump.

"That took hours of standing on a slanted board while they applied it," she said. "All great things that help you make this sort of wacky fun character."

Although her resume is stacked with thrillers and dramas, she knew "St. Vincent" would be a great addition to her repertoire.

"It's a balancing act," she said. "But I've always just had the taste that I have and I'm always looking to work with great material and great film makers, great actors in both of these movies."

"St. Vincent" is in theaters now.