I was watching the 1999 "Three's Company, Three's A Crowd" Entertainment Tonight special on TV tonight and I saw Audra Lindley on there and wondered "Did she wear a wig on Three's Company?" I've seen her on "Matlock", "The Mommies", "Friends", and "Cybill", but her hair is more of a light blonde shade than the curly red hair that Helen Roper had!

As Helen Roper, Audra Lindley wore a wig.

Mwah hahahahaha i never knew that.
I saw her on a 1989 episode of Tales from the crypt and her hair was sort of a whitish blond

Here is a good picture of her as a blonde from her Another World days, on which she played Elizabeth Matthews #2. The picture I believe was taken sometime from 1964 to 1969:

http://www.igs.net/~awhp/ffat93.jpg