Fresh off Below’s big success, Josh Hartnett boards Elle Fanning’s star‑studded biopic

So Josh Hartnett is genuinely not wasting any time following the thunderous reception for Below. Next stop: he’s landed a key role alongside Elle Fanning in Moonsong: A Life In Seven Verses, one of those rare biopics already causing a stir in the film world before anyone’s even seen a frame. The project has barely started selling internationally yet, but the names attached are frankly eye-watering.

Production for Moonsong is scheduled to get underway in May 2027.

Stacked Cast, Loaded Crew

Right, let’s talk about the line-up, because it reads like a festival red carpet. Rebecca Miller is on board to direct this biopic about Margaret Wise Brown – yes, the writer responsible for those classic children’s books you probably had forced on you as a kid. Elle Fanning leads as Brown, and Hartnett will play ‘Big Bill’ Gaston, a socialite swept up in one of Brown’s passionate affairs. The supporting cast is one of the wildest I’ve seen announced in a while: Emma Thompson, Sally Hawkins, Danny Huston, Robert Aramayo, and Chloe Pirrie are all confirmed. But the real curveball is Julianne Moore, set to play the poet Michael Strange, whose intense (and, apparently, somewhat destructive) influence is meant to shape Brown’s creative life.

• Elle Fanning – Margaret Wise Brown
• Josh Hartnett – Big Bill Gaston
• Julianne Moore – Michael Strange
• Emma Thompson, Sally Hawkins, Danny Huston, Robert Aramayo, and Chloe Pirrie all in supporting roles

1930s New York, High Drama

The story’s set in 1930s New York, right in the thick of the city’s bohemian creative circles. Brown discovers her spark for writing children’s stories – but she’s not just bashing out cutesy tales. She basically brings a whole new sensory approach to the genre, mixing with a weird and wonderful crowd of avant-garde artists and educators. Expect plenty of dramatic swings between innocence and daring, and no shortage of romantic tangles. Apparently, Brown’s fiercely protective of her creative independence, which plays out in spiky relationships and the odd scandal as well.

Miller actually adapted the script herself, pulling from Leonard S. Marcus’s biography Margaret Wise Brown: Awakened by the Moon. She describes Brown as someone shockingly modern for her time: perpetually childlike on one hand, but a trailblazer in publishing, with over 100 books chalked up. Miller’s fairly effusive about Fanning in the lead, reckoning she’ll turn Brown into a role model for anyone trying to embrace every part of themselves without trimming away their odd edges.

Behind the Camera

In case all that wasn’t enough, the technical team’s equally stacked. Jarin Blatchke, best known for his work on The Lighthouse, will be behind the camera. Creature effects and puppets (!) are in the hands of Neal Scanlan, who’s won an Oscar for that sort of thing. The costume designer is Malgosia Turzanska (also Oscar-nominated), and the production design comes from Kim Jennings. No less than Martin Scorsese himself is exec producing, with Round Films and Damon Cardasis handling the rest of the producing side.