A cuckoo bird in a cuckoo clock!!!
This is actually the back side of the costume, but Miss G made her entrance backwards so it is what the audience saw first. Initially the door was closed, and when Miss rocked from side to side the pendulum swung. Then, at the sound cue, the door opened for the cuckoo to pop out, and a confetti cannon fired feathers all over the ball floor. The timing of this photo is perfect because you can see the smoke and feathers from the cannon! Then on the next sound cue:
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Now Ball 39 is just a memory, and we all rest for as long as we can stand it, until we just have to start planning Ball 40! It takes a full year to pull this off, so we'd better not rest too long!