Katy Vail in 1956

The daughter of Laurence Vail, a French-American sculptor, and Kay Boyle, an American writer (The Crazy Hunter, Monday Night), Katy studied with Henri Rolland at the French conservatory. She was very active in dubbing where her roles include GrandMa Addams in The Addams Family and Addams Family Values, Thelma in Inspector Gadget, Yetta in The Nanny. She dubbed many actresses in English or French such as Charlotte Rampling in Georgy Girl, Jill St John in Batman, Sheree North in Maniac Cop. She was also an artistic director for the dubbing of Boy Meets World, Good Morning Mis Bliss and other productions.

On-screen, she was Sylvette in The French, They Are a Funny Race, and she is occasionnally seen on French and British TV.

In the third French version of Snow White and the Seven Dwarfs, she was the voice of the Queen after her transformation, and she reprised the role in the series House of Mouse. For Walt Disney, she also was the voice of Grandmother Willow in Pocahontas 2: Journey to a New World.