Benicio del Toro and Laura Dern have joined the cast of "Star Wars: Episode VIII," Lucasfilm and Disney announced, without disclosing any details about their roles.

Principal photography began on the movie in London Monday.

Returning for the film are franchise icons Mark Hamill, Carrie Fisher and Anthony Daniels, as well as Adam Driver, Daisy Ridley, John Boyega, Oscar Isaac, Andy Serkis, Lupita Nyong'o and Domhnall Gleeson, who starred in the blockbuster seventh installment, "Star Wars: The Force Awakens."

Written and directed by Rian Johnson, the as-yet-untitled next picture is set for release Dec. 15, 2017.

"Rey took her first steps into a larger world in 'Star Wars: The Force Awakens' and will continue her epic journey with Finn, Poe, and Luke Skywalker in the next chapter of the continuing 'Star Wars' saga, 'Star Wars: Episode VIII,'" the official 'Star Wars' website said.