TOD: The most awkward, funny thing I ever experienced on stage happened to me in college. I was the "Wayne of Morse' in a production of "MacBird."
Part of my costume was a ginormous spear I carried with me on all entrances.
The opening strains of the "William Tell Overture" were supposed to be the sound cue for my first entrance. Night after night, cues were assembled and used but never mine, and I had to do them myself.
One night near the end of rehearsals I waited for my cue. It did not come. The director yelled out to tell me I missed my entrance. I yelled back that I didn't miss my entrance because MY DAMNED CUE NEVER PLAYED.
I was told to go on as usual...and, yet again, I did the "William Tell"....
...and as I proceeded to march onto the stage, I tripped just at the edge of the scrim...and all the rehearsal audience saw was my spear hit the stage floor...and bend.
I was humiliated and the entire cast and crew erupted into hysterical laughter.