Surprise! Lady Gaga appeared from behind a plumage of pink peacock feathers to the delight of Olympic fans during the Opening Ceremony in Paris on Friday.App users can click here to watch her surprise performance. Along the River Seine, Gaga kicked off her performance of Zizi Jeanmaire's French song “Mon Truc En Plume.” She was accompanied by a troupe of eight dancers carrying pink feather fans.The Grammy- and Oscar-winning performer then moved to the piano. Gaga's act was pre-recorded and then shown on the television broadcasts.Her appearance was a surprise – she was not listed on a program provided to the media in advance – but was heavily rumored after the singer and actor was spotted in Paris.For the first time in the history of the Olympic Summer Games, the Opening Ceremony did not take place in a stadium.Instead, the parade of athletes was held on the Seine River with boats for each national delegation. These boats were equipped with cameras that allowed television and online viewers to see the athletes up close.