Kevin Costner Thinks ‘Yellowstone’ Franchise Is ‘Not Going to Work’ Without ‘His Genius’

Kevin Costner galloped away from Yellowstone — but he's obsessively eyeing the hit's multiple TV spinoffs and griping the shows are doomed to fail without his valuable input, sources exclusively tell Life & Style .

Kevin, 69, scored a Golden Globe for portraying patriarch John Dutton on the wildly popular Western, which lasted five seasons — but sources say he butted heads with creator Taylor Sheridan , 54, over scheduling and left to shoot the first installment of Horizon: An American Saga , his widely panned Western epic.

Now, sources say he is smarting over his passion project's lackluster reviews and poor box office returns.

"Kevin's well aware the likes of Taylor Sheridan and other turncoats are probably chuckling over Horizon 's bad viewing numbers, and it's only strengthened his bitterness and dislike toward them," an insider says.

"It would give him a lot of quiet satisfaction seeing those guys fall flat on their faces for even attempting to breathe fresh life into the show he sees very much as his baby — not theirs," the insider adds.

Entertainment sources say Taylor is expanding Yellowstone 's empire with The Madison , which will star Michelle Pfeiffer , Kurt Russell and Patrick J. Adams — adding to the already existing prequels 1883 , 1923 and 1944 .

But the insider says, "At the end of the day, Kevin thinks the Yellowstone bosses are running around like delusional headless chickens. His bottom line, however egotistical it may sound, is that without his genius — even on a consulting level — it's not going to work."