LuPone, who guest-starred on "American Horror Story: Coven" last season, will "play a mysterious character of great importance in Vanessa’s (Eva Green) past," according to an announcement from the network.
LuPone is a two-time Tony Award winner for Evita and Gypsy.
La Cage aux Folles Tony Award winner Douglas Hodge has also joined the cast, guest-starring as "an intense Scotland Yard investigator on the hunt to discover who is responsible for the terrible murders that have been plaguing London."
Joining the second season as series regulars are stage and screen actors Helen McCrory ("Harry Potter and the Deathly Hallows," As You Like It, Medea) and Simon Russell Beale ("MI-5," Uncle Vanya, King Lear). Tony Award nominee Sarah Greene (The Cripple of Inishmaan) and Jonny Beauchamp have also signed on as guest stars.
Written by Tony-winning playwright John Logan (The Last Ship, Red, I'll Eat You Last), the second season of "Penny Dreadful" begins filming in Dublin this month. The season will air in 2015. The cast also features Josh Hartnett ("Black Hawk Down"), Timothy Dalton ("The Living Daylights"), Eva Green ("Casino Royale,"), Reeve Carney (Spider Man: Turn Off the Dark), Rory Kinnear ("Skyfall"), Billie Piper ("Doctor Who"), Danny Sapani ("Trance") and Harry Treadaway ("The Lone Ranger").
According to Showtime, "Some of literature's most terrifying characters, including Dr. Frankenstein, Dorian Gray, and iconic figures from the novel Dracula are lurking in the darkest corners of Victorian London. 'Penny Dreadful' is a frightening psychological thriller that weaves together these classic horror origin stories into a new adult drama."
Logan created the series that he executive produces along with Oscar winner Sam Mendes ("American Beauty, Cabaret) and Pippa Harris ("Revolutionary Road," "Call The Midwife"), both of Neal Street.