It was towards the end of Act II during a production of The Sound of Music. The lights grew dim upstage of the scrim, as the scenery began to move. Franz, the butler, was coming off stage with a café table on casters, and he was almost into the wing, when the porch floor beneath him began to move - a second too soon. Suddenly the table was tipped onto it’s side, and a silver tray of food, a …