u/BerryKiss1316

i'm looking for a behind the scenes episode/clip where a group of stage performers/extras are getting ready to portray people under the sycorax's control. There is a female body movement/ dance coach showing them how to walk with a blank expression. later we see the stage performers in action as the orchestra is behind them playing the music from said scene in the christmas special where everyone who's A+ goes up onto the roofs. i watched behind the scenes episode this when i was younger and it's driving me mad that i can't find it. i believe it's from a stage show/special pre 2010. any help is much appreciated, thank you.