It’s official: Kevin Costner will not be returning to television’s hit neo-Western, “Yellowstone,” for its final episodes or for any future “Yellowstone” offshoot, ending speculation about his involvement with one of TV’s biggest hits in recent years.

In a video posted to social media on Thursday evening, Costner said that after a year and a half working on his upcoming multifilm epic, “Horizon,” and thinking about “Yellowstone,” which he called a “beloved series that I love that I know you love,” he realized he would not be able to continue. The second half of Season 5, the show’s last, is set to debut Nov. 10.

“It was something that really changed me,” Costner said of “Yellowstone,” which premiered on Paramount Network in 2018 and became an instant and durable standout. It was TV’s highest-rated drama of the 2021-22 TV season, and its Season 4 finale was the most-watched scripted prime-time telecast in 2022, Variety reported.

“I just wanted to let you know that I won’t be returning,” said Costner, 69, telling fans that he has loved the relationship they have been able to develop. “I’ll see you at the movies.”

A representative for Costner did not immediately reply to a request for further comment Friday.

The announcement comes after will-he-or-won’t-he rumors about whether Costner would continue in the role of ruthless Montana rancher John Dutton, which earned Costner a Golden Globe for acting in 2023. Tensions between Costner and the show’s creative team had been reported for more than a year — to the point that it was largely expected that Costner would not be involved in the conclusion of “Yellowstone.”

In an emailed statement Friday, a representative for Paramount Network said that those at the network wished him the best with the film series and that they had hoped that they would continue working with him. “Unfortunately,” the statement read, “we could not find a window that worked for him, all the other talent and our production needs in order to move forward together.”

Last year, Taylor Sheridan, who with John Linson created “Yellowstone,” essentially confirmed that Costner would soon be departing the show, telling The Hollywood Reporter that he was “disappointed” by Costner’s decision. “It truncates the closure of his character,” he said. “It doesn’t alter it, but it truncates it.”

Before “Yellowstone,” Costner was primarily a movie star and had only dabbled in television. In 1991, he won two Oscars for the sweeping Western “Dances With Wolves,” which he directed, co-produced and starred in.

“Horizon,” which he stars in and is directing, producing and co-writing, explores the settling of the West after the Civil War. After “Horizon: An American Saga — Chapter 1” comes to theaters June 28, the second chapter is expected to arrive in quick succession, on Aug. 16. The third movie is being filmed in Utah. Costner confirmed that he has already paid $38 million of his own money to finance the project.

A sequel for “Yellowstone,” also created by Sheridan, is in the works and is expected to premiere on Paramount Network in December. The show already has two prequels: “1923,” which stars Helen Mirren and Harrison Ford, premiered in December 2022 (it was renewed for a second season); and “1883,” a 10-episode miniseries, ended in February 2022.