The pair, who along with Jessica Lange have starred as different characters in the past two seasons of the show, will play new people again next season.
"What Season 3 is about is more historical in nature," TVGuide.com reported Murphy said after a screening of the Season 2 finale. "I'm also interested in getting into a horror romance. That's certainly something that's going to be in the water for Season 3."
Murphy said the third outing will take place in several cities and jump back and forth in time, the television news website said.
Season 1 was set in a haunted house in California, while Season 2 took place in a 1960s-era insane asylum in Massachusetts.
Murphy said Season 3 will be lighter than its predecessors.
"You're going to see a very different tone in Season 3," TVGuide.com reported Murphy said. "As a person right now, I do feel lighter and wanting to embrace something a little bit more fun. I want to do something next season that's funnier. I really miss that Jessica Lange as [Season 1's] Constance, and I know she missed it, too."