From Diane Keaton’s memoir Then Again, here’s a letter she wrote to her mother during the Broadway run of Woody Allen’s Play It Again Sam:
February 18, 1969
Dear Mom,
It seems like you were just here. How did it go by so fast? Isn’t Woody hilarious? Did you really like the play? I couldn’t exactly tell. Woody does a lot of let’s say unusual things onstage, things you wouldn’t think a person of his stature would do. Last night, in the middle of a scene he suddenly started impersonating James Earl Jones in The Great White Hope. I tried not to laugh, but it was impossible.

