...during a live performance of Hamlet

https://www.metv.com/stories/richard-boone-once-fell-off-the-stage-into-the-orchestra-pit-during-a-live-performance-of-hamlet

Boone used to share this anecdote with friends.

When he was a professor, Richard Boone told his students not to become actors (https://www.metv.com/stories/richard-boone-told-his-students-not-to-become-actors-when-he-was-a-professor)

Boone gave some strongly worded advice.