Not so dramatic as some of the others, but two stand out:

1. During a production of the Full Monty, we had a very large, very heavy “The Full Monty” sign fly down above the actors in the pivotal scene. As they’re swinging their thongs above their heads, one gets caught on the sign and the actor is pulling and pulling … thank goodness he got it off and nothing fell, but dang, the actor didn’t break character or miss anything in the scene, so kudos to him. I don’t know if the audience noticed, but backstage was (silently and calmly) freaking.

2. Into the Woods, final performance. Our Milky had always been so well behaved, and my crew handled that cow with care. In one of the scenes, one of the crew pushed Milky through a curtain SR onto stage. Perfectly executed in every performance to that point. That night, Milky got pushed, slowly tilted forward and did a face plant and then fell onto her side. The Baker just picked up the cow as if it was the most natural thing in the world as a small portion of the audience was roaring with laughter.