
With the Yellowstone Ranch behind him, Dutton joins an elite unit of U.S. Marshals, combining his skills as a cowboy and Navy SEAL to bring range justice to Montana. Kayce and his teammates -- Pete Calvin, Belle Skinner, Andrea Cruz, and Miles Kittle -- must balance the high psychological cost of serving as the last line of defense in the region's war on violence with their duty to their families.

When a former cop launches a killing spree against those he blames for sabotaging his career, the Marshals close in and one of their own finds themselves in the crosshairs of the vengeful killer; Rainwater faces mounting political pressure and backlash over his leadership on the reservation; Belle struggles to keep her family life stable.