‘Horizon: An American Saga’ gambles on bringing Kevin Costner’s western dream to the big screen

Nobody has done more to keep the western flame kindling on the big screen than Kevin Costner, but the audacity of his latest rodeo – a planned 12-hour story for theatrical release, spread over four parts – feels like overreach, if not outright folly. “Horizon: An American Saga - Chapter 1” teems with old-fashioned values, but the prospect of nine more hours to reach the journey’s end might have looked daunting even to intrepid pioneers.

In some respects, testing the kind of longform storytelling associated with limited series in a theatrical format – with part two of “Horizon” set to premiere just seven weeks after this first installment – represents a bold, perhaps even necessary gamble. The fact that Costner, as director, producer, co-writer and star, has ponied up by investing his own money in the project makes that dice roll even more conspicuous.

Yet “Horizon” tells such a sprawling story that this introductory chapter, despite strong moments, proves especially scattered, rolling out numerous characters on separate fronts without connecting them. Costner himself doesn’t arrive on screen for an hour, and just when there’s a sense the threads might start to coalesce, an entirely new one emerges regarding a wagon train.

While there have been other “To be continued” movies lately, those have been built around established franchises, like “Mission: Impossible,” “Fast & Furious” and “Spider-Man: Across the Spider-Verse.” Attempting to do so with an original idea is, by any measure, a big ask, even from western fans inclined to give Costner – thanks to “Open Range,” “Wyatt Earp” and “Dances With Wolves” – the benefit of the doubt.

Beginning in 1859, “Horizon” serves as the name of a town being sold as the embodiment of the American dream and manifest destiny to pioneers, with enticing promises of “virgin land” and a better future leading to an ill-advised settlement that prompts a swift and brutal raid from a rogue Native-American band.

Elsewhere, Costner’s laconic cowboy gets reluctantly drawn into a dispute involving a young child, forcing him and the woman who watches the boy, Marigold (Abbey Lee), to go on the run, while the aforementioned wagon train grapples with its own issues.

The sprawling cast includes several of Costner’s former co-stars (Will Patton, Jeff Fahey and James Russo among them), as well as Sienna Miller, Sam Worthington, Luke Wilson, Jamie Campbell Bower and Michael Rooker.

Unlike westerns of old, Costner also seeks to portray the frontier with greater complexity, from providing the Native-American perspective to touching upon bigotry against the Chinese and the encroachment of the Civil War.

All that might work more effectively as a Ken Burns documentary, however, than it does as a movie, at least in this initial form. And while “Horizon” closes with what amounts to a coming attraction for what lies ahead, set to John Debney’s soaring score, the connections forged with this sprawling roster of players don’t ensure the level of investment that will bring people back for more.

Costner has underscored his commitment to “Horizon” by walking away from “Yellowstone,” a modern western that has bookended a near-40-year career of stardom that began with “Silverado.” With little left to prove, he has earned the right to take chances, which might explain why Warner Bros. (like CNN, a unit of Warner Bros. Discovery) signed on as his distribution partner in this venture.

Practically speaking, though, if Costner really intends to finish 12 hours of “Horizon,” the logical home for the second half of it would be back on television, via the studio’s HBO, rather than a theatrical setting.

Because while it’s easy to applaud Costner’s ambitions, based on “Horizon’s” part one, that’s where this American saga belonged from the opening gun.

“Horizon: An American Saga - Chapter 1” premieres June 28 in US theaters. It’s rated R.

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