"Kathy Bates is running the Hotel. #AHSSeason5," Murphy tweeted, without revealing any other details.
Bates joined the franchise in American Horror Story: Coven -- the third installment in the anthology series and won an Emmy for her performance. She also appeared in Season 4, American Horror Story: Freak Show.
Each season features many of the same core cast members, but playing different characters in new settings with changing supernatural themes.
The fifth season -- American Horror Story: Hotel -- is to premiere on FX this fall, with Lady Gaga as part of the ensemble.