We can go on talking about racism and who treated whom badly, but what are you going to do about it? Are you going to wallow in that or are you going to create your own agenda?
Some of the most amazing human beings on the face of the planet go to sci-fi conventions, although I'm sure a few of them wouldn't admit it.
I don't know how it is now but the assistant stage manager had to understudy several parts. You had to be ready to go on at any time if the actor couldn't make it to the play. I didn't think anything of it.

