As of now, fans may be curious about Horizon: An American Saga, the project that seemingly drew Costner away from Yellowstone season 6. It’s a sprawling western saga with multiple installments, featuring Costner in both acting and directing roles. The initial two parts are slated for release this summer, with the first hitting screens on June 28th and its sequel following on August 16th. Alongside Costner, the cast includes Sienna Miller, Danny Huston from Yellowstone, Jena Malone (a former co-star from Hatfields and the McCoys), Sam Worthington, and others.