Most of the scripts for the sophomore season of the Neil Gaiman drama have already been completed.

There's a change at the top of Starz's American Gods.

Showrunners Bryan Fuller and Michael Green have stepped down from the Fremantle-produced Neil Gaiman drama. A replacement has not yet been determined. Starz declined comment. Sources say Fuller and Green — who developed the series for TV — had creative differences with producers Fremantle over the show's (rapidly expanding) budget.

Fuller and Green had already written most of the scripts for the second season of the high-concept, hyper-stylized drama. An episode count for the second season was never announced after the series scored a fast renewal at the premium cable network.

American Gods had a long and challenging road to TV. The adaptation was originally set up at HBO in 2011 with Tom Hanks' Playtone banner attached. HBO ultimately passed on the drama before Starz and Fuller came on board in 2014. The project received a series order the following year. Originally ordered for 10 episodes, the show underwent multiple rewrites with Fuller scrapping multiple episodes and reworking others. What's more, Fuller was juggling American Gods and CBS All Access' Star Trek: Discovery — the latter franchise having been a dream job since he was a kid — and exited the latter to focus his attention on the Starz show. He next has anthology Amazing Stories set up as one of tech giant Apple's first scripted forays. Green, meanwhile, is one of the hottest writers in town. He is developing Brian K. Vaughan's beloved comic Y: The Last Man at FX and executive producing Netflix's superhero show Raising Dion. On the feature side, he penned screenplays for Logan, Blade Runner 2049 and Murder on the Orient Express. And the latter are just this year alone.