Stranger Things actor David Harbour has stepped down from his upcoming film Behemoth! after several months of production. Originally set to star alongside Pedro Pascal and Olivia Wilde, Harbour’s reason for leaving remains undisclosed. Filming for the project commenced in October 2025, with the storyline shrouded in secrecy but rumored to center around a cellist.
While details of Harbour’s role were scarce, reports suggest that Will Arnett will now fill the vacancy in the Searchlight Pictures movie, joining Pascal, Wilde, Eva Victor, and Matthew Lillard. According to sources cited by Deadline, reshooting due to the cast change is expected to be minimal, as Harbour had only filmed a few scenes, primarily due to commitments with the Stranger Things series five promotional tour.
The concluding episode of Stranger Things was unveiled on January 1, marking the culmination of the decade-long show. Playing the role of police chief Jim Hopper, Harbour’s character became entangled in supernatural mysteries within Hawkins, Indiana, investigating the disappearance of character Will Byers, portrayed by Noah Schnapp.
The fifth series, which served as the show’s finale, aired in segments starting late in 2025 and concluding in January. Harbour was occupied with a global press tour leading up to the first volume’s premiere, participating in various promotional events, including Netflix’s ‘Stranger Things Day’ celebration on November 6.
During this period, Harbour faced personal scrutiny following the release of his ex-wife Lily Allen’s album, West End Girl. The album hinted at their past, suggesting Harbour pushed for an open marriage after Allen’s theatrical success, leading to allegations of infidelity with an individual referred to as Madeleine.
While Allen acknowledged elements of the album as fictional, she maintained that some parts were rooted in reality. Harbour has yet to address the album’s implications or respond to accusations of infidelity. Harbour and Allen were married for four years, with the actor previously reflecting on his life choices in an interview with Esquire Spain.
Harbour’s representatives have been approached for comment regarding his departure from Behemoth!.