The third installment in Kevin Costner’s magnum opus, the Horizon: An American Saga franchise, faces an uncertain future, and it’s not clear if it can survive the first two chapters’ box office woes and delays. Horizon has long been a passion project for Costner. He first commissioned scripts for the film in the 1980s, and to actually get them made, Costner spent millions of dollars on Horizon. Even Costner’s own money may not be enough to see the franchise to its end, however, especially after Chapter 1‘s lackluster box office performance – it earned just $38 million worldwide, well short of recouping its budget (via Box Office Mojo).

https://screenrant.com/is-horizon-3-movie-still-happening-kevin-costner/