Kevin Costner, 69, is dapper as ever at Horizon: An American Saga premiere while costar Sienna Miller is stylish in a white dress as they lead the stars

Kevin Costner and one of his stars, Sienna Miller, put on a glamorous performance as they arrived at the premiere of his new Western film Horizon: An American Epic: Chapter 1.

The 69-year-old director, co-writer and star followed his announcement that he had finished his hit series Yellowstone by turning the spotlight on his new multi-part epic.

He was joined at the premiere by several stars from Horizon, including Sienna Miller, who looked casual yet cool in a beautiful white dress.

Despite the high-profile nature of Costner’s epic – which he envisions as four films in total – the Western is currently feared to flop at the box office after being expected to earn just $12 million at the domestic box office in its opening weekend, despite Costner has contributed approximately $38 million of his own money to the passion project.

Kevin Costner and one of his stars, Sienna Miller, put on a glamorous performance as they arrived at the premiere of his new Western film Horizon: An American Epic: Chapter 1