Sienna Miller, Sam Worthington to lead Kevin Costner's 'Horizon'

Jamie Campbell Bower will also feature in the movie in a pivotal role

siennamf Sienna Miller | IMDB

Actors Sienna Miller and Sam Worthington have boarded the cast of Hollywood veteran Kevin Costner's upcoming directorial "Horizon".

  A period Western film, the project will be Costner's first feature as a director since 2003's "Open Range".

The movie, which will start production later this month, is a saga spanning 15 years both before and after the Civil War expansion and settlement of the American West.

Besides Miller and Worthington, "Stranger Things" star Jamie Campbell Bower will also feature in the movie in a pivotal role.

Costner, 67, wrote the script for Horizon with Jon Baird. He will also produce and finance the film through his Territory Pictures production company. Casting for the film will begin in February.

Miller, known for movies such as "American Sniper", "Foxcatcher" and "Layer Cake", recently completed filming "My Mother's Wedding" opposite Scarlett Johannsson and Kristin Scott Thomas. 

She will also star in "Raised Eyebrows", opposite Geoffrey Rush and Charlie Plummer, and Apple TV+ anthology series "Extrapolations". 

Worthington most recently appeared in Hulu crime drama "Under the Banner of Heaven" and is currently looking forward to the release of "Avatar: The Way Of Water", the sequel to his 2009 blockbuster "Avatar"