Judy Greer and Mark Hamill board the upcoming adaptation of Stephen King's The Long Walk

More cast members have been added to Lionsgate's upcoming adaptation of the 1979 Stephen King novel (published under his pen name Richard Bachmann) The Long Walk.

According to Deadline, Judy Greer and Mark Hamill are the latest additions to the cast. The Long Walk marks one of two King projects Hamill is working on as he will also star in The Life of Chuck, adapted from one of the author's novellas published in his If It Bleeds collection. Greer has also previously worked on a King adaptation, playing the supportive teacher Rita Desjardin in the 2013 remake of Carrie that starred Chloë Grace Moretz and Julianne Moore.

Interestingly, Deadline says that The Long Walk features a competition where "50 boys" must maintain a speed of 3 miles per hour or more, lest they face the consequences. However, in the original novel, the competition involves 100 boys and the speed they have to maintain is 4 mph.

It's a relatively minor detail, but I imagine Deadline might be pulling from the Lionsgate source, which might mean they are changing these details for the movie. That would make sense, as casting 100 extras would be significantly more expensive than casting only 50 or so.

But the gist of the book's plot is the focus on this "Long Walk," a competition implemented by the ruling totalitarian regime in a dystopian America that forces 100 teen boys to embark on a long walk along U.S. Route 1. Throughout their journey on foot, they have to maintain a speed of 4 mph without stopping. If they fall below that speed for too long, they receive a warning. Three warnings and the soldiers shoot them dead.

The film will be directed by Francis Lawrence (The Hunger Games: The Ballad of Songbirds & Snakes) with a screenplay from JT Mollner (Strange Darling). Previous cast announced include Cooper Hoffman, David Jonsson, Jordan Gonzalez, Roman Griffin Davis, Charlie Plummer, and more.

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