A Montana Inheritance begins the morning after the last performance of the 2019 National Finals Rodeo, where Rusty Blackstone was crowned World Champion steer wrestler. Rusty and his girlfriend, Amanda, are reeling from his former girlfriend, Jenny's revelation that Todd is Rusty's five-year-old son. Jenny's ex-husband and Rusty's lifelong enemy, Warren Weston, claims Todd as his own. Rusty is not sure whether to believe Jenny, but he wants to know for sure. Because Warren and Rusty's sister, Corinne, are in a serious relationship, Rusty worries that this new twist could cause big problems in his family.
This is partly the story of rodeo in the year of Covid-19. In March, in the middle of the Houston rodeo, the mayor shuts it down because of the epidemic and most of the other early season rodeos cancel as well.
Rusty retreats to New Mexico where he stays with his father, who convinces him to try to win the Professional Rodeo Cowboys Association's Linderman Award if the season resumes. This requires success.