FX’s adaptation of Y: The Last Man has suffered another setback, as sources say the lead role of Yorick will be recast, Collider has exclusively learned.

Rising star Barry Keoghan (The Killing of a Sacred Deer) had been cast as Yorick Brown, who finds himself as the last living male on Earth after a cataclysmic event wipes out every other man on the planet. With the help of his pet monkey Ampersand, Yorick sets out to find his girlfriend Beth, and together they end up traversing a post-apocalyptic world in which women call the shots.

Based on the comic book by Brian K. Vaughan and artist Pia Guerra, the long-gestating series is set to explore themes of “gender, race, class and survival.” Last summer, Eliza Clark (The Killing) was brought in to replace original showrunners Aïda Mashaka Croal and Michael Green, who exited the project due to “creative differences.”

Y: The Last Man already boasts a top-notch female cast that includes Diane Lane, Imogen Poots, Lashana Lynch, Juliana Canfield, Marin Ireland and Amber Tamblyn. Lane will play Yorick’s mother, a U.S. Senator. It’s unclear whether the series remains on track for a late 2020 release, or if we’ll have to wait until early next year for it.

Keoghan broke out in 2017 with back-to-back turns in Christopher Nolan‘s Dunkirk and A24’s psychological thriller The Killing of a Sacred Deer. He went on to star in the excellent indie movie American Animals and HBO’s award-winning miniseries Chernobyl. Keoghan will soon be seen as Druig in Marvel’s Eternals, and he has also wrapped David Lowery‘s Green Knight, which A24 will release later this year. Sources did not provide a reason for his exit.

FX is set to unveil Alex Garland‘s new series Devs on March 5, while the fourth season of Fargo will debut later this year. The network is also developing a new take on Stephen King‘s Carrie, as Collider first reported.