News surrounding the upcoming high energy thriller flick Boy Kills World has been breaking through seemingly everyday now. Earlier this week, it was revealed that Famke Janssen, Brett Gelman, and Sharlto Copley would be stepping into the roles of members of the Van Der Koy family, and now Deadline reports that Michelle Dockery will be joining the tight-knit clan as sister Melanie.

Like the rest of her family, Melanie is cutthroat and brutal, ready to bulldoze anyone in her way. For Melanie, things can get especially violent when her family’s values are challenged and the cracks in their framework are revealed for what they truly are. Backed by her mother Hilda (Janssen), Gideon (Gelman), and Glen (Copley), Melanie sees her loved ones as the end all be all in the post apocalyptic battleground surrounding Boy Kills World.

The project comes to us from the mind of Moritz Mohr, a German filmmaker who will see Boy Kills World as his feature directorial debut. Taking place in a harsh dystopian universe, the film will tell the story of Boy (Bill Skarsgård), a deaf/mute man that creates joy in his sad reality through his colorful imagination. Tragedy strikes when his family is slaughtered, leading the young man on a life changing and threatening journey into the deeply forested jungle. There, he makes an unlikely ally in a shaman (Yayan Ruhian) who takes Boy under his wing. With the shaman as his mentor, Boy begins to learn how to leave his childhood behind and become a masterful and silent assassin, ready to take on those who have wronged him in the past and who threaten his future.

Downton-Abbey-Michelle-Dockery
Image Via ITV

RELATED: 'Boy Kills World': Jessica Rothe Replaces Samara Weaving in Fantasy Action Thriller

The film will also star Jessica Rothe, Andrew Koji, Isaiah Mustafa, and twins Cameron and Nicholas Crovetti. Action superstar filmmaker Sam Raimi is attached to the film as a producer alongside Zainab Azizi under Raimi Productions, with Vertigo Entertainment’s Roy Lee, Nthibah Pictures’ Simon Swart and Wayne Fitzjohn, Hammerstone Studios’ Alex Lebovici, with Stuart Manashil and Dan Kagan also producing. Ventaro Film’s Reza Brojerdi and Andrew Childs will serve as executive producers. Arend Remmers and Tyler Burton Smith penned the thriller’s screenplay.

Known worldwide for her performance as Lady Mary Crawley in Downton Abbey, Dockery received one Golden Globe nomination and three Primetime Emmy nominations for her work on the period drama. Fans can next catch her in Netflix’s Anatomy of a Scandal which will hit the streamer on April 15. She will also be reprising her role as Lady Mary Crawley in the upcoming film, Downton Abbey: A New Era, landing on U.S. theater screens May 20.