The increasingly sprawling cast list for Star Wars Episode 7 has just added two more names: 12 Years a Slave's Lupita Nyong'o and Game of Thrones' Gwendoline Christie. They join original Star Wars trio Mark Hamill, Harrison Ford and Carrie Fisher, along with John Boyega, Adam Driver, Oscar Isaac and Domhnall Gleeson.

Nyong'o won the best supporting actress Oscar for her role as Patsey in the Steve McQueen directed 12 Years a Slave, and has been touted for a role in Episode 7 for some time.

Gwendoline Christie in Game of Thrones. Photograph: Sky

British-born Christie plays the warlike Brienne of Tarth in the hit HBO series Game of Thrones, but has had little exposure to cinema audiences so far. This will change, however, after the release of the final two parts of The Hunger Games series, in which she plays rebel leader Commander Lyme.

It is not known yet which roles the actors will play, but they join a line-up that was announced with some fanfare in April by the film's director JJ Abrams. Filming began on April 7, and the expected release date is 18 December 2015.

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