Why ‘Stranger Things’ Star Sean Astin Was Replaced By Brian Geraghty On ‘The Alienist’

“Stranger Things” actor Sean Astin is no longer part of the cast of TNT’s upcoming event series, “The Alienist.”

Astin was replaced by Brian Geraghty for the role of Theodore Roosevelt due to scheduling difficulties. According to Deadline, Astin had been shooting “The Alienist” in Budapest while also filming “Stranger Things” Season 2 in Atlanta. But the back-and-forth traveling to and from Hungary and the U.S. proved to be tremendously hard to work out, so Astin ultimately exited the project.

Geraghty, who currently plays Officer Sean Roman on NBC’s “Chicago P.D.,” confirmed the recasting on Instagram with a photo of Roosevelt.

READ: How Sean Astin is honoring his mother Patty Duke after her death

This isn’t the first time someone has been replaced on “The Alienist.” In April 2015, Deadline reported that “True Detective” director Cary Fukunaga would direct all the episodes of the series. But a year and half later, it was announced that Jakob Verbruggen replaced Fukunaga as director due to scheduling conflicts. Despite his exit as director, Fukunaga remains an executive producer on the series.

Based on the novel of the same name by Caleb Carr, “The Alienist” is a thriller drama set in 1896 New York, where a series of gruesome murders of boy prostitutes has caught the attention of the public. Newly appointed New York City police commissioner Roosevelt (Geraghty) calls upon Dr. Laszlo Kreizler (Daniel Brühl), a criminal psychologist — a.k.a. alienist — and newspaper illustrator John Moore (Luke Evans) to solve the disturbing killings in secret. Joining them in the investigation is Sara Howard (Dakota Fanning), a headstrong secretary at the police headquarters.

Also starring on “The Alienist” are Robert Wisdom, Q’orianka Kilcher, Matt Lintz, Matthew Shear and Douglas Smith. In addition to Fukunaga and Jakob Verbruggen, other executive producers on the series are Hossein Amini, Eric Roth, Steve Golin and Rosalie Swedlin.

“The Alienist” author, Carr, is also on board as consulting producer. “After twenty years of tough struggle and countless failed attempts, I’m delighted that Paramount Television, Anonymous Content and TNT have decided to join forces and bring ‘The Alienist’ to life in what, based on the material I’ve read, has the potential to be a faithful and exciting TV series,” Carr said in a statement to Variety in 2015. “The array of talent already gathered for the project, for whom I’m pleased to be acting as consultant producer, is deeply impressive … It’s my hope and expectation that, working together, we can all make this effort meet the standard expected by the very patient fans of the book, whose loyalty I consider a trust that I personally will do everything I can to protect.”