Patti LuPone is back for more “Penny Dreadful.”

The Broadway legend, who guest starred as Joan Clayton (aka the Cut-Wife) in the sophomore season of Showtime’s Victorian England-set horror series, is back for season 3 as a series regular. She’ll also be playing a new role: Dr. Seward, an American therapist who treats Eva Green’s bewitching Vanessa Ives with an unconventional new approach.

The third season, which returns in 2016 with nine episodes, will also be adding another familiar name to the list of literary characters who appear on the show. Shazad Latif (“The Second Best Exotic Marigold Hotel”) will play an interpretation of Robert Louis Stevenson’s Dr. Henry Jekyll.

“Penny Dreadful” has also added Wes Studi as a series regular. The “Hell on Wheels” and “Red Road” alum plays Kaetenay, an intense, enigmatic Native American with a deep connection to Ethan (Josh Hartnett). He also becomes an ally to Sir Malcolm (Timothy Dalton).

Guest stars also include Christian Camargo as Dr. Alexander Sweet, a zoologist who strikes up an unlikely friendship with Vanessa; Sam Barnett as Dr. Seward’s mysterious young secretary; and Jessica Barden as Justine, a young acolyte to Lily (Billie Piper) and Dorian Gray (Reeve Carney).

“Penny Dreadful” is created, written and executive produced by John Logan and executive produced by Logan’s Desert Wolf Productions, along with Oscar winner Sam Mendes and Pippa Harris, both of Neal Street Productions. It is a co-production of Showtime and Sky.