Harry Potter star Emma Watson is returning to fantasy cinema after signing on to play the lead in "Game of Thrones-style" saga Queen of the Tearling, reports Variety.

Watson will play 19-year-old idealistic princess Kelsea Glynn, created by Erika Johansen after the author heard a 2007 speech by a pre-presidential Barack Obama. Johansen signed a seven-book deal in February and the first novel in the series is due next year. It is set three centuries after an environmental catastrophe, when a malevolent Red Queen reigns over the kingdom of the Tearling. Glynn must defeat the monarch to reclaim her deceased mother's crown, and publishers have compared the tone of the series with that of George RR Martin's A Song of Ice and Fire saga, which is being adapted by US network HBO as Game of Thrones.

Warner Bros, which oversaw the Harry Potter films, has acquired film rights to the entire book series. Watson will reunite with David Heyman, who also produced the Potter saga. The British actor recently appeared in teen drama The Perks of Being a Wallflower and has a supporting role in Sofia Coppola's much-hyped The Bling Ring. She can be seen playing a version of herself in the dark comedy This Is the End, Seth Rogen and Evan Goldberg's humorous apocalypse movie, which is released in US cinemas on 14 June and arrives in the UK later in the month. Watson will also play Noah's adopted daughter Ila in Darren Aronofsky's forthcoming biblical epic.