The Marsh King's Daughter is a 2023 American psychological thriller film directed by Neil Burger and written by Elle Smith and Mark L. Smith, based on the 2017 novel of the same name by Karen Dionne. It stars Daisy Ridley, Ben Mendelsohn, Garrett Hedlund, Caren Pistorius, Brooklynn Prince, and Gil Birmingham.

The Marsh King's Daughter was released in the United States on November 3, 2023, by Lionsgate and Roadside Attractions.

Two years before Helena was born, the Marsh King abducted her mother, and she spent her childhood in captivity. Now convinced he will try to take her daughter, Helena sets out to outmaneuver the man who taught her everything she knows about surviving in the wilderness.

The project was announced in February 2018, with Elle Smith and Mark L. Smith writing the screenplay for director Morten Tyldum. Alicia Vikander was cast in the lead role, and was also set to serve as an executive producer.^[2]

Filming was due to begin in late July 2019, and continue through autumn,^[3] but no further developments were announced until February 2021, with Tyldum and Vikander no longer involved in the film. Neil Burger was now directing with Daisy Ridley cast to star, replacing Tyldum and Vikander.^[4] In May, Ben Mendelsohn joined the cast.^[5] In June 2021, Brooklynn Prince, Gil Birmingham, Caren Pistorius, and Garrett Hedlund joined the cast of the film.^[6][7]

Filming began on June 7, 2021, in Ontario, Canada.^[6][8][9] Filming officially wrapped on August 6, 2021.^[10]

Initially meant to be released by STXfilms, the film's distribution was shopped to different distributors following the dissolution of STXfilms' domestic distribution company:^[12] eventually, STXfilms formed a domestic distribution partnership with Lionsgate, Lionsgate and Roadside Attractions scheduling the film for release on October 6, 2023.^[13] It was later delayed to November 3, 2023, to avoid competition with Taylor Swift: The Eras Tour.^[14] Amazon Studios will distribute the film in European markets as part of ErosSTX's multi-year output deal with the company via Prime Video.^[15][16]

The Marsh King's Daughter was released on digital platforms on November 21, 2023, followed by a Blu-ray and DVD release on January 2, 2024.^[17]

On the review aggregator website Rotten Tomatoes, 41% of 46 critics' reviews are positive, with an average rating of 5.5/10. The website's consensus reads: "The Marsh King's Daughter begins with plenty of promise and has a remarkable cast, but they're outweighed by the story's dawdling pace and clumsy conclusion."^[18] Metacritic, which uses a weighted average, assigned the film a score of 47 out of 100, based on 14 critics, indicating "mixed or average" reviews.^[19]