According to this source: http://m.ibtimes.co.in/american-horror-story-hotel-full-cast-list-revealed-who-are-you-most-excited-see-poll-630237   Gaga is called Elisa Starr  Gaga plays the role of a popular lounge singer, who is pitted against Lolita and is always competing with her for popularity.   (that role is being played by Angela Bassett).