That's Kevin Costner's Son Hayes, 15, Making His Acting Debut in the Horizon: An American Saga Trailer

Kevin Costner's son Hayes is making his big-screen debut!

The 15-year-old appears in the first trailer for his father's upcoming two-part epic Western Horizon: An American Saga, which was released Monday.

Hayes stars in a tense scene that shows him helping a woman (played by Sienna Miller) and young girl, who are presumably his mother and sister, into a shelter through an opening in the floor as their home is attacked.

"It's all right — I'm gonna be with Dad," he tells Miller's horrified character, before closing the door on their hiding spot.

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Costner — who co-wrote, directed and stars in Horizon — told PEOPLE in November 2022 that his son, who was 13 at the time, is "very good" in the film.

"Hayes plays the namesake character that I actually play in the movie. He's 13 years old and the screenplay's been around longer than that," said the Dances with Wolves actor, 69.

While acting certainly runs in the family, Costner — who also shares son Cayden, 16, and daughter Grace, 13, with ex-wife Christine Baumgartner (Costner is also dad to daughters Annie and Lily, and sons Joe and Liam from previous relationships) — joked that casting his son also gave him an excuse to spend more time with Hayes.

"I kind of did it on purpose, so he could be hanging out with me," he told PEOPLE at the time. "And the same thing for Cayden, same thing for Grace. I'm like any other parent, I'm trying to figure out, like, 'This is really neat. You should come be with me.' "

Per a synopsis, Horizon "explores the lure of the Old West and how it was won — and lost — through the blood, sweat and tears of many."

"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," the synopsis adds.

Aside from Costner, Hayes and Miller,42, Horizon's cast also includes Sam Worthington, Jena Malone, Abbey Lee, Michael Rooker, Danny Huston, Luke Wilson, Isabelle Fuhrman, Jeff Fahey, Will Patton, Tatanka Means, Owen Crow Shoe, Ella Hunt and Jamie Campbell Bower.

Horizon: An American Saga Chapter 1 is in theaters June 28, followed by Chapter 2 on Aug. 16.