Kevin Costner's epic western Horizon: An American Saga -- Chapter 1 will make its debut on Max Aug. 23. Costner wrote, directed and starred in the film, which is intended to be the first installment of a trilogy. The cast includes Sienna Miller, Sam Worthington, Giovanni Ribisi, Abbey Lee, Will Patton, Jena Malone, Michael Rooker, Danny Huston, Luke Wilson, among others. The film "explores the lure of the Old West and how it was won -- and lost -- through the blood, sweat and tears of many," a synopsis from the streamer said. "Spanning the four years of the Civil War, from 1861 to 1865, Costner's ambitious cinematic adventure will take audiences on an emotional journey across a country at war with itself, experienced through the lens of families, friends, and foes all attempting to discover what it truly means to be the United States of America."