Marshals, the new Yellowstone spin-off featuring Luke Grimes, follows Kayce Dutton as he embarks on a “new beginning” by joining an elite U.S. Marshals team in Montana. Returning cast members are Brecken Merrill, Gil Birmingham, and Mo Brings Plenty. Creator Spencer Hudnut emphasizes that Monica’s death highlights real-life health issues while respecting her character, setting the stage for an emotional and purposeful narrative.