Luke Grimes leads the new era as Kayce Dutton — with Rainwater, Mo, and Tate returning, but no Monica in sight

The Dutton Legacy Lives On in Y: Marshals

The Yellowstone universe is expanding again — and fans just got their first full look at what’s to come. In the brand-new trailer for the upcoming spinoff Y: Marshals, Luke Grimes returns as Kayce Dutton, stepping into a brand-new frontier of justice, violence, and family conflict.

Premiering March 1, 2026 on CBS and streaming next day on Paramount+, Y: Marshals follows Kayce as he leaves ranching life behind to join an elite U.S. Marshals unit in Montana. Their job? To take on violent gangs, drug cartels, and even grizzly bears in the state’s harshest backcountry terrain.

Fan Favorites Return — and One Is Growing Up Fast

The trailer delivered some welcome surprises. Gil Birmingham returns as Chief Thomas Rainwater, offering Kayce a chilling observation: “All Duttons are born killers. But you… you’re a protector.”

We also catch a glimpse of Brecken Merrill as Tate Dutton, now noticeably older. The teen, last seen in Yellowstone Season 5, is shown in a car — older, more serious, and clearly still central to Kayce’s life.

Mo Brings Plenty is also confirmed to reprise his role as Mo, Rainwater’s trusted right-hand man, according to Deadline.

But one key character is missing: Monica Dutton. Played by Kelsey Asbille, Monica was a core part of Kayce’s emotional arc. Her absence from the trailer — and from casting announcements — has sparked speculation.

Who’s Joining the Team?

Several new faces will join Kayce in Y: Marshals, including:

• Ash Santos as Andrea

• Tatanka Means as Miles

• Arielle Kebbel as Belle

• Brett Cullen as Harry Gifford, head of the U.S. Marshals in Montana

• Logan Marshall-Green as Pete Calvin, Kayce’s former military buddy

Together, they form a unit tasked with delivering “range justice” in a state where law and violence go hand-in-hand. But as the trailer teases, the job comes with a steep psychological cost.

Kevin Costner’s Exit and What It Means for the Franchise

Y: Marshals also arrives in the wake of Kevin Costner’s departure from Yellowstone. His character, John Dutton, was killed off after filming only the first half of Season 5. Rumors swirled about behind-the-scenes tension, but Grimes addressed the change directly in a recent interview.

“Hopefully everyone can see that it was time,” he said. “It was actually the easiest season we’ve filmed.”

Although he hasn’t spoken to Costner since the show ended, Grimes was clear: “There’s no hard feelings… he’s Kevin Costner. He’s a big deal.”

The Question Fans Are Asking: Where’s Monica?

While Rainwater, Mo, and Tate are back, Monica’s fate is still unclear. Is she being held for a surprise arc later in the season? Or has something happened to her off-screen?