Co-star David Harbour has left the production of Andor creator Tony Gilroy’s drama, Behemoth! Will Arnett is said to be his replacement. In October 2025, filming got underway on Behemoth!, a feature-length drama from Andor creator Tony Gilroy. It was announced at the time that Pedro Pascal is to star, with Stranger Things actor David ... Behemoth! | David Harbour exits Tony Gilroy’s film drama during shooting
Co-star David Harbour has left the production of Andor creator Tony Gilroy’s drama, Behemoth! Will Arnett is said to be his replacement.
In October 2025, filming got underway on Behemoth!, a feature-length drama from Andor creator Tony Gilroy. It was announced at the time that Pedro Pascal is to star, with Stranger Things actor David Harbour joining him that same month.
It’s now being reported that Harbour has left the project, however, with production company Searchlight Pictures rushing to find a replacement. According to Deadline, it’s Will Arnett taking over from Harbour – he’ll join a cast which also includes Olivia Wilde, Matthew Lillard and Eva Victor.
Harbour was previously busy promoting Stranger Things' expensive final season, and so it’s thought that while reshoots will be required, his involvement in the production so far has been relatively small.
Arnett was most recently seen in Bradley Cooper’s comedy drama, Is This Thing On?, which he both co-wrote and starred in; before that, he’s enjoyed a long career of comic performances and voice work, including the gruff tones of the Caped Crusader in The Lego Movie and The Lego Batman Movie.
Little is known about Behemoth! at this stage, though Gilroy’s track record as a dramatist and director of smart thrillers means it’s rightly anticipated. Beyond his hit Star Wars TV spin-off, Andor, Gilroy was previously the screenwriter on the Bourne movies, and both wrote and directed the slow-boiling legal thriller, Michael Clayton, in 2007.
Not that Behemoth! is a thriller, necessarily; there isn’t so much as a logline publicly available at present, but it’s thought the plot has something to do with a cellist. We were quietly hoping that the title and its accompanying exclamation mark might mean that Gilroy’s moved into 1950s giant monster territory, but that now sounds unlikely. Maybe we’re talking about a really, really big cellist here?
We’ll bring you more on Behemoth! as it comes in.
Read more: Stranger Things season 5 | A spoiler-filled deep dive into the new season
