viewers. Just as impressive, the show saw double-digit gains in all demos, including a growth of 52 percent among adults 18-34 for a cumulative rating of 5.6 among adults between ages 18-49, or 7 million viewers. And it averaged 11.5 million viewers for season five over seven days of viewing.

So where were all those millions of Yellowstone fans over the June 28-30 weekend when Costner’s big-budget movie Horizon: An American Saga — Chapter One rode into more than 4,000 theaters across North America? Most were a no-show for the film, which Costner, co-wrote, directed and stars in.

The movie opened to just $11 million, a dismal start for an event title that cost $100 million to produce. In terms of headcount, that means roughly 1 million people turned out, according to leading entertainment research firm EntTelligence. That compares to 3.6 million for A Quiet Place: Day One and 5 million for Inside Out 2.

By the end of the weekend, all of Hollywood was wondering how the opening might impact Horizon: An American Saga — Chapter Two, which is set to open in no fewer than six weeks on Aug. 16 (tickets are already on sale). Insiders say there are no plans as of now to change the second film’s release. Exhibition execs say the same. Other sources add that it’s too soon to declare Horizon Chapter One a box office dud, and that — like a slow-moving tumbleweed — it still has time to find its audience.

Costner is known for his confidence, but even he shocked Hollywood when he announced he would direct for the first time in decades and make four Horizon movies chronicling the great migration West during the Civil War era. When no studio would back his vision, the Dances With Wolves Oscar winner cobbled together financing for the first two movies — including $38 million of his own money, an undisclosed sum from two mystery investors and proceeds from selling off rights to foreign distributors. In April, Warner Bros. signed on as a distributor and announced the unprecedented plan to release Chapter One — which sports a running time of three hours and one minute — and Chapter Two less than two months apart. Costner, who ultimately left Yellowstone amid his Horizon commitments, is also on the hook for marketing costs.

Costner believed his film would strike a nerve in America’s heartland — just as Yellowstone has — and while it indeed played best in the mountain regions, Midwest, South and South central states, it so far has failed to galvanize his fans or Yellowstone viewers to the desired degree.

Costner and Warners always knew Horizon would skew older, but that demo isn’t enough to support a big-budget event pic. More than 60 percent of ticket buyers were over age 45, including 47 percent over 55, according to PostTrak exit surveys. Rarely does a film skew that old. Among other demos, only 11 percent of ticket buyers were between ages 18-24, followed by 14 percent for ages 25-34 and 11 percent for ages 35-44.

The 55-plus crowd isn’t known for rushing out to see a movie on opening weekend, and it’s possible Horizon Chapter One could enjoy a strong multiple. Yet even if it does three times its opening number, it would still be deemed a theatrical failure financially and will lose tens of millions of dollars unless it does well on premium VOD and other home entertainment or ancillary platforms. Premium VOD, which usually costs $20 per rental, could be a boon for Horizon, notes Comscore chief box office analyst Paul Dergarabedian.

“The streaming potential down the road is huge for this franchise,” he says, adding Horizon “has appeal among the older demographics, for whom this type of movie is in their wheelhouse.”

As of the time this story went to press, Costner hadn’t commented on the film’s initial performance. Heading into the weekend, he told Entertainment Weekly it’s misguided to put all the focus on a movie’s opening weekend gross. “If we put so much pressure on that, we’re bound to be disappointed. I’m really happy that Horizon looks like what it’s supposed to look like, and that’s the way it’ll look the rest of its life. And that’s really important to me in this process.”

Horizon — Chapter One is also making a big push overseas after making its world premiere at the Cannes Film Festival, but so far, there’s no word as to how it’s faring in the markets where it launched tied to its North American debut (Warner Bros., which is handling the film in the U.K., didn’t report opening numbers, suggesting it didn’t do much business). Westerns can be a tough sell, both overseas and in North America.

The fate of the third and fourth Horizon movies isn’t clear since they aren’t a part of the distribution deal with Warner Bros., meaning they could end up a streaming service. Costner has shot a few days on the third film and will resume production in August. At Cannes in May, he said he would need to find more financing to complete the third film.

On June 20, just days before Horizon — Chapter One opened, Paramount announced that the second half of the fifth and final season of Yellowstone — sans Costner — will debut Nov. 20. The next day, Costner posted a message to his fans on Instagram explaining why they won’t be seeing him, along with a gentle nudge to see Horizon.

“It was something that really changed me. I loved it, and I know you loved it,” said the Costner. “I love the relationship we’ve been able to develop, and I’ll see you at the movies.”