Deadline is reporting that Sienna Miller and Sam Worthington have signed on to star in Horizon joining previously announced cast members, Kevin Costner and Jamie Campbell Bower. The film, which is being described as a historical epic about the American frontier, is a project close to Costner’s heart and will see him not only star but also return to the director’s chair for the first time since 2003. Filming is set to begin later this month.

The story of Horizon is said to cover a fifteen-year span of time that will include “pre-and post-Civil War expansion and settlement of the American West.” Through a variety of perspectives, the story will explore interactions with the Indigenous people native to the American West before the arrival of colonizers seeking to settle the land and claim it for themselves, as well as the dangerous conditions created by the natural elements of the time. It is also being reported that Horizon is the first film in a planned trilogy.

Miller is an actress likely best recognized for her roles in such films as American Sniper, Foxcatcher, and Layer Cake. She recently starred in the recent Netflix drama Anatomy of a Scandal. Worthington is best known for starring in Avatar — which over a decade later still holds the highest global box office — and will be returning for the sequel later this year. He also starred in the critically acclaimed Hulu crime drama Under the Banner of Heaven.

Both actors gave statements on their casting with Worthington saying: “I am very excited and humbled to go on this incredible and important journey with Kevin, who is one of the industry’s finest and inspiring storytellers.” Miller added: “I am so excited to go on this epic journey with such a legendary actor and director at the helm. The story is riveting. I am very honored to be a part of it.”

Costner is an Academy Award-winning director with his directorial debut, Dances with Wolves, also winning best picture. Costner wrote the script for Horizon with Jon Baird. It’s clear that this film is a passion project of Costner’s, with him starring, directing, writing, producing, and personally financing the film. Costner is producing the film through Territory Pictures with Warner Bros. and New Line set to release the film.

Horizon is set to begin filming in Utah at the end of the month. Stay tuned to Collider for any updates on the project.

via Collider