From a longtime reader:

In 1987, I worked as a development officer for a policy organization in Washington. We created a fundraising dinner and invited Charlton Heston to MC the thing. But I could not get a reply from anyone. Time was running out; we needed to go with our number 2 pick if Heston was not going to do it.
I called National Review’s office and asked for William Rusher. To my surprise, he picked up the phone. I told him my plight. He said, “My boy, you shall have an answer from Mr. Heston within 5 days!” And, I did. Heston wrote me a sincere apology and an explanation that he could not accept our invitation.
Rusher did not know me and certainly did not need me. He was kind and helpful to someone who could never do anything for him.