Musicals like The King and IWest Side Story, and My Fair Lady delighted us both visually and musically, becoming instant classics. But while most of us can sing every word to “I Feel Pretty” and “I Could Have Danced All Night,” it may surprise you to learn that the voice you are singing along with belongs to a woman you may have never heard of.

Soprano Marni Nixon had become a sought-after singer by the time she was a teenager due to her perfect pitch and ability to read even the most difficult pieces of music. She had already done some dub work in Hollywood when she got a call that would change her life.

The singer passed away Sunday at the age of 86 from complications from breast cancer, but her legacy will live on for generations to come.

NPR has the full story.