That was over 31 years ago in 1990.
Today she is 75, and has starred in 59 movies in total, 36 since The Godfather: Part III was released.
In The Godfather: Part III, I think Diane Keaton looks:
The Godfather: Part III scores 7.2 out of 10 on The Movie Database.
Diane Keaton's first acting role was as 'Joan Vecchio' in Lovers and Other Strangers, released in 1970 when she was 24.