Kate is surprised when suddenly, the quest at her wedding broke into an unexpected flash mob dance she couldn’t control herself and she is amused and excited at same. She can’t control herself because she freaked.
Her reaction was mixture of excitement, surprise, she got overwhelmed by emotion at some point when one of the dancers go closer to her, the bride kept jumping up and down and bridegroom keep looking at her cause absolutely she cannot contain her excitement.
I think everyone is excited about her reaction on the video, the organizer were very successful because they got that element of surprise since to her she was not expecting music to be that soon, as seen in the video the husband was aware because he doesn’t react as compared to the bride. Finally, when one of the quest picked her to join them on the dance fall, she dances with all her energy. i love that at last she join the dance.