The egger's name is Natalie Holt. She was playing viola (or something of the sort) for the singers and had decided that she would take that moment to get back at Simon for not making it on to the talent show the year prior.
The 30-year-old [Natalie] is quoted by The Mirror as saying: "I want to apologise to Richard and Adam for overshadowing their performance. I’ve never done anything like this before and in hindsight I have realised it was a silly thing to do."
Seriously, the best part is the opera singer dudes who don't even flinch. Come on...someone have SOME SORT of reaction.
In my opinion, it added a little something interesting to the performance.
Watch the video here: