FX and Hulu's long-gestating television adaptation of Vertigo Comics' Y: The Last Man has officially begun production, albeit with the key roles of Agent 355 and Hero Brown being recast.

Per an official announcement from FX, Y: The Last Man started production in Toronto, Canada this week. Additionally, secret agent and secondary protagonist Agent 355 will now be played by Ashley Romans (NOS4A2, Shameless). Meanwhile, Hero Brown -- the sister of main protagonist Yorick Brown -- will now be played by Olivia Thirlby (Juno, Dredd). 355 and Hero were originally slated to be played by Captain Marvel's Lashana Lynch and 28 Weeks Later's Imogen Poots, respectively.

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Y: The Last Man is certainly no stranger to major recastings. Originally, the role of Yorick was to be played by Eternals' Barry Keoghan. However, Keoghan ultimately had to depart the role, with Ben Schnetzer -- known for his roles in Warcraft and Punk's Dead: SLC Punk 2 -- stepping up to play the eponymous "Last Man." That said, other cast members have remained attached to Y throughout its development process, including Diane Lane (Jennifer Brown), Marin Ireland (Nora Brady), Juliana Canfield (Beth Deville) and Amber Tamblyn (Kimberly Cunningham). They will be joined by the likes of Diana Bang as Dr. Allison Mann and Elliot Fletcher as Sam Jordan.

Based on the Vertigo/DC comic book series of the same name by Brian K. Vaughan and Pia Guerra, Y: The Last Man "traverses a post-apocalyptic world in which a cataclysmic event decimates every mammal with a Y chromosome but for one cisgender man [Yorick] and his pet monkey [Ampersand]. The series follows the survivors in this new world as they struggle with their efforts to restore what was lost and the opportunity to build something better." FX explains that the show's first two episodes will be written by Eliza Clark and directed by Louise Friedberg, and that "[a]ll episodes of the season will be directed by women and the production has a significant number of female department heads, including both DPs, the production designer, costume designer, casting director, editors, stunt coordinator and more."

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Y: The Last Man has had a long journey to screens. After plans for a film adaptation of Vaughan and Guerra's text fell through, FX began developing a TV series based on the comic -- simply titled Y -- in 2015. A pilot went into production in August of 2018 and Y was officially ordered to series in February of 2019. However, the series then had to replace not only its lead actor, but also its showrunners. It was later revealed that the show's title had been changed to Y: The Last Man and that it would stream under the FX on Hulu banner. It is expected to arrive sometime next year.

FX's Y: The Last Man stars Diane Lane as Congresswoman Jennifer Brown, Ashley Romans as Agent 355, Ben Schnetzer as Yorick Brown, Olivia Thirlby as Hero Brown, Amber Tamblyn as Kimberly Cunningham, Marin Ireland as Nora Brady, Diana Bang as Dr. Allison Mann, Elliot Fletcher as Sam Jordan and Juliana Canfield as Beth Deville. The series is set to premiere under the FX on Hulu banner in 2021.

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