A heartbreaking tragedy from Mo Brings Plenty’s family has helped inspire a new episode of Marshals, bringing a deeply personal story to the Taylor Sheridan universe.

Mo Brings Plenty, who plays Mo, Chairman Rainwater’s right-hand man and blood brother to Kayce Dutton, will be at the center of the Sunday, Nov. 15 episode. The story draws from the 2024 death of his nephew, Cole Brings Plenty, who appeared in Sheridan’s 1923.

A coroner ruled out foul play in Cole’s death, but his family disagreed with that conclusion.

Executive producer Spencer Hudnut said he spoke with Mo before moving forward with the storyline to make sure he was comfortable with the idea.

“Before pursuing it, I spoke with Mo to see if he’d be comfortable with portraying the story and he was welcoming to the idea,” Hudnut said.

Hudnut had already been considering a story in which a former teammate of Kayce’s dies under mysterious circumstances, forcing Kayce to prove that the death was a murder rather than a suicide.

The writers changed many details between the real-life tragedy and the episode, but Hudnut acknowledged that the storyline remains closely connected to Mo’s personal experience.

In the episode, the body of Mo’s nephew is discovered, and Kayce refuses to let the sheriff quickly dismiss the death as suicide. Kayce and Broken Rock tribe member Miles, played by Tatanka Means, decide to bend the rules as they investigate what really happened.

“These are two Marshals who are willing to go into the grey area, especially when it’s someone they’re so close to in Mo,” Hudnut explained.

The investigation also highlights the challenges Kayce and Miles face while trying to uncover the truth. They encounter prejudice and ignorance surrounding issues affecting the reservation, while the lack of cameras and witnesses makes investigating a crime scene in a state park even more difficult.

Hudnut revealed that Troy’s murder will not be solved immediately.

“Troy’s murder is definitely an engine that will be resolved later in the year and could potentially be tied to a larger conspiracy,” he said.

The episode also puts Kayce into another difficult situation when his son, Tate, gets beaten up after trying to stop his girlfriend from being harassed.

The attackers soon face Kayce’s anger as he reacts to what happened to his son.

“There will definitely be consequences [for the dust up] — maybe not legal ones, but very personal ones that heavily impact Kayce’s own individual journey, and the journey of his relationship with Tate this season,” Hudnut said.

Meanwhile, Kayce’s boss Cal and colleague Belle face a major change in their relationship.

Belle secretly travels to Salt Lake City to be with Cal while he undergoes cancer treatment. Away from Montana, their workplace and the people watching their every move, the two finally have a chance to confront feelings they have kept hidden.

“Cal and Belle are finally out of Montana and away from prying eyes and their work lives, which frees them up to explore things in a way they haven’t been able to do at the office,” Hudnut said.

Cal’s battle with cancer also makes him more vulnerable, allowing him to open up to Belle. In return, Belle begins sharing more about her own past.

That emotional connection eventually pushes the two to act on their feelings. But once they return to their normal lives and face the pressures of their jobs again, their relationship could become much more complicated.

Marshals airs Sundays at 8/7c on CBS.