Answer
Sienna Miller starred in the film The Lost City of Z, directed by James Gray. The film is based on the 2009 book of the same name by David Grann. It follows the story of British explorer Percy Fawcett, who ventured into the Amazon rainforest in the early 20th century in search of a lost city. Miller played Fawcett's wife, Nina. The film was released in 2016 to critical acclaim.