Natalie Dormer is ready to get her demon on for Showtime.

The Game of Thrones favorite has been tapped to star in the premium cable network's Penny Dreadful revival, City of Angels.

Penny Dreadful: City of Angels, which will feature all new characters and storylines, opens in 1938 Los Angeles, a time and place deeply infused with social and political tension. When a grisly murder shocks the city, Detective Tiago Vega (Daniel Zovatto) is embroiled in an epic story that reflects the rich history of Los Angeles: from the building of the city's first freeways and its deep traditions of Mexican-American folklore, to the dangerous espionage actions of the Third Reich and the rise of radio evangelism. Before long, Tiago and his family are grappling with powerful forces that threaten to tear them apart.

Dormer will topline the series as Magda, a supernatural demon who can take the appearance of anyone she chooses and who manifests in a number of guises throughout the story. The character is a dangerous enemy and invaluable ally. Dormer joins a cast that also includes Jessica Garza (The Purge) and Johnathan Nieves (New Amsterdam).

Dormer spent six seasons as Margaery Tyrell on HBO juggernaut Game of Thrones. The Penny Dreadful role brings the actress back into the Showtime fold after she starred as Anne Boleyn on the cabler's The Tudors. Her credits include Picnic at Hanging Rock, The Scandalous Lady Woman and Elementary. On the feature side, her credits include starring and co-writing In Darkness, The Forest, The Hunger Games franchise and Captain America: The First Avenger.

Series creator John Logan and his Desert Wolf Productions banner, Michael Aguilar (Kidding) and Neal Street Productions duo Sam Mendes (American Beauty, Skyfall) and Pippa Harris executive produce the series; James Bagley co-exec produces. Paco Cabezas (Penny Dreadful, The Alienist) will direct multiple episodes. Production will begin this year. A premiere date has not yet been determined.

Dormer is repped by UTA, United Agents, Untitled Entertainment and Jackoway Austen.