Yellowstone star Luke Grimes was “heartbroken” to learn character Monica Dutton would be killed off in 2026 spin-off Marshals.

Grimes returns as Kayce Dutton in the hit Western franchise. His on-screen wife however, played by Kelsey Asbille, was killed off in the explosive premiere of the new series.

“I was not at all expecting that when I got the call that that’s their idea,” Grimes told Entertainment Weekly. “And I felt two things simultaneously.”

“For a while I couldn’t imagine doing it without her,” he revealed as he spoke of his close friendship with Asbille.

“I was like, ‘That doesn’t even make sense. Kayce and Monica are the same thing. They’re one.’ But I also realised, well, there’s a big story there.”

Grimes understood the need for a shakeup to help move the narrative, after Yellowstone‘s finale saw Kayce and Monica’s happy ending.

“Obviously, we can’t just watch this guy have his dream life. There’s no drama,” Grimes told the online publication.

Something big would have to happen for Kayce to pick up his badge again.

“The last time we saw him, he was throwing a badge in a field. Is he gonna go pick it up?” he said. “I did think it was a good idea, even though it was heartbreaking.”

Grimes said he “worked up the courage” to call his former co-star and tell her about Monica’s on-screen death.

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“We had a great conversation,” he told TVLine at the time. “In true Kelsey fashion, she handled it like a pro and totally understood.”

Fans predicted a major death in the spin-off when the official trailer for Marshals was released in January this year.

Notably absent from the trailer, below, was Monica Dutton. Instead, fans were met with Kayce and son Tate (Brecken Merrill) tearfully watching a body being covered up at home.

“So I’m assuming they kill off Monica to grow Kasey’s character because she didn’t want him to go back to the gunslinger ways,” one fan shared their theory at the time.

“Ya’ll took out Monica? Well… time for unhinged Kayce to make a return. And I’m HERE for it,” another fan reacted.

Season 1 of Marshals picks up after the events of the Yellowstone finale as Kayce Dutton and son Tate grapple with grief on the ranch.

With his own “demons to conquer” the series follows Kayce’s decision to join an elite unit of U.S. Marshals, combining his skills as a cowboy and military background to bring justice to Montana range.

However, the Dutton family name sure comes with a lot of skeletons in the cupboard.